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I still find it baffling that people want to risk getting locked up in a quarantine on a cruise ship like during COVID.
Don't forget norovirus, the gift that keeps on giving
The collab everyone has been waiting for: Princess Cruises + Chipotle - Norovirus on the High Seas
As someone who has virus induced asthma where a simple cold can leave me wheezing and coughing for weeks, I was very careful about not catching Covid before the vaccines came out.

But once it became apparent that they don’t prevent you from catching Covid. But do reduce the severity, I got the J&J one shot early on and boosted based on the recommendations and went on about my life - including getting on a cruise to hang out with two other couples we hadn’t been able to spend time with in awhile.

I caught Covid that Wednesday and didn’t even realize it because my symptoms were mild, it really was “no worse than the cold” (fully vaxxed). If I had suspected Covid, I would have been more careful around other people.

We prescheduled a Covid test when we got back.

Two of our friends who were also vaxxed had it a lot worse . All of us said we would do it again just for the chance to hang out together.

That being said, with our current lifestyle (https://news.ycombinator.com/item?id=36306966) I’m kind of over cruises and I would hate to be stuck in isolation on a cruise ship if I had Covid which I would voluntarily do just to be considerate.

But I am going on one with my adult sons who we don’t see as much any more because of our current traveling (see link). It’s a cheap all inclusive get away just to hang out with friends and family.

Might be better off just instituting pollution taxes and not letting ships fly whatever flags they want or burn whatever oil they want. Then if cruises can clean up, good for them.

I can't read the article btw

Pollution taxes are country by country. Cruise ships just change the country’s flag they fly to avoid them.
Tax them where the pollution takes place not matter the flag
I suspect ports need the cruise ships more than the cruise ships need ports.
Depends on the port. It's not like there are two Venices in the world.
This is harder than it seems, there are international treaties that "regulate" (read: de-regulate) what companies can do regardless of the country.

Also in many cases a particular city, say Barcelona or Venice, may want to regulate, but pollution laws are typically at the regional or national level.

Maybe Barcelona and Venice should enlist privateers to sink any cruise ships that come too close.
That is Hard To Do, and not the only problem with the industry (the other glaring one is labor).
yes, but is it actually harder than Stopping Cruises, which is what the activists apparently want? Obviously not.
There are some things that are just plain Bad and should be illegal, like theft.

There are other things that aren't really great for us, but we (well, some of us) derive pleasure from them, or some of us do. Like alcohol, tobacco, cannabis, eating beef, and so on.

The best thing to do with those is not outlaw them, but tax them.

[flagged]
Soon it will be hard to find reasons to be alive. Can’t go outside because it’s 120 degrees. Can’t go for a hike because of the smoke and wildfires. Can’t drive to the store because of the flooding. Can’t buy food because the crops failed.
Seriously, if you believe that to happen soon, then it will happen irrespective of anything we do now because that change is already in the system. At that point, not enjoying the time now as much as possible would be a waste - so no reason to reduce anything anymore.
only if you care about what happens to the next generation
How much improvement would there even be for the next generation? Marginal - and the unborn don't get a voice.
Doc Smith would find that assertion embarrassing, I think.

The good news is that across the world, this sort of hand-flapping is being ignored. In reality, we have already begun doing the right thing. We're already averting the worst-case scenario. But that isn't a repair job. We're slowly the rate of getting-worse. We have to do more to arrest that, to get to a net-zero state and then a net-negative state, because we can't predict that whoever we stick with the check will then be in as advantageous a place as we are to pull that brake.

This has immediate and short-term benefits even if one is too selfish to care about our grandchildren and great-grandchildren. Within living memory, rivers in the United States were too foul in which to swim and now, for the most part, they're not. Cities in the West were choked with smog and now, for the most part, they're not. And bringing it back to the topic at hand: cruise ships foul the ports they land in; you can smell it on shore and the trash they leave in their wake is obvious, and as a side benefit they also have extremely disproportionate climate impact. "What if...we didn't do that?" is not a difficult question and not one to rend one's shirt over.

Doing the right thing is better for us, now, as well as for our descendants.

I am not the doomer, I was outlining the consequences of a doomerist position (and there is indeed historical precedent on how people reacted to impeding doom like the plague).

I'm aware of current progress (worked there myself a bit) and past successes on environmental issues.

What 'voisin described is the near-future state for many places and and in some places the current state. It isn't remotely controversial to describe our current El Nino situation as median twenty years' hence.

The only reason to trot out "well if you believe that, why would we do anything at all?" is to discourage action because it isn't perfect.

Is it so hard to imagine that you need to campaign in ways that work across large sections of society and around the globe?

Some places somewhere will have this near future state, others will not.

This article is seemingly more about NOx, not CO2. It should be relatively easy to address the NOx problem as technology exists. I think if the activists narrowly focused on this, they might actually be able to get somewhere.
I’m glad they are focusing on other pollutants. Lots of people go from ships pollute a lot to they produce a lot of CO2, when they really make other pollutants and are pretty efficient for CO2.

Article also mentioned sulfur oxides. Those should get better as ships are forced to convert to low sulfur fuel,

Concretely, the activists should chant: “GT DLE LNG” (drum beat) “GT DLE LNG” (drum beat) “GT DLE LNG”

All of the local air quality concerns would disappear if their protest is effective.

GT : Gas Turbine DLE: Dry / low emission LNG: liquefied natural gas

Your reasons for living are eating meat and being crammed in small spaces with lots of other people?
We should make partying illegal. Alcohol, smoking, drugs, overeating, loud music etc. All of these are bad for you and providing the goods hurts the environment.

Stop partying. You're destroying the planet when you do.

Nobody needs to party.

This is whataboutism that fails to engage with the argument. Lots of things are potentially bad, we should consider the tradeoffs when prompted. In this case, we're discussing cruise ships, not <insert other thing>.
It’s a piss poor reason to ban something because “it serves no utilitarian value. But we aren’t going to fight For changes to the much larger commercial shipping industry that is causing the same type of harm”
This is also whataboutism, because it implies we cannot walk and chew gum at the same time.
The article specifically said they aren’t targeting commercial shipping. Before making up meaningless arguments, at least read the article. They specifically said they aren’t “walking” and “they are just chewing gum”
Ah, so I must solve all problems that impact my desired end state? This sounds perilously familiar, are you in my management chain?

Like, snark aside, I said "we", not "they", intentionally. There's a whole lot of people working on these problems. That these folks aren't targeting commercial shipping does not mean in the slightest that it's not happening. When I go to town meetings and say "hey, high-density housing is good for [town]!", it's not somehow less legitimate that I'm not going to the next town over and advocating for it there, too.

Again, they specifically said they are going after them because “Cruises don’t serve any purpose”. It’s like saying we are going after cigarettes for causing cancer. But not going after asbestos because cigarettes “don’t serve a purpose”.

No matter how you try to spin it, it’s a stupid argument.

It's not about "solving" the problem. It's about taking away something people enjoy that you happen to not care about. If we take this to its logical conclusion then everything you do for enjoyment will also call under the umbrella of "no utilitarian value".
Here's how considering trade-offs went for the people in the article:

"I don't like cruises. Cruises also cause harm. Let's ban cruises."

They're okay with banning cruises because they don't like them. Well, I don't like parties, so let's ban them too.

It's easy to "give up" things you don't enjoy, but you don't get to decide what other people enjoy. Maybe cruises to other people are the highlight of their life. You don't know that. You can't know that.

Every reason you give to take something away that people like they will eventually use on things you like.

Whether you need to party or not, you will need to consider the specific details. Smoking goes into the air. Some drugs will also go into the air. Music also goes into the air but only temporarily and it can easily be isolated.

You should not just make everything illegal, because you will need freedom of speech, too.

It's not like there is actually a meaningful movement to stop eating meat and flying, or even cruises.
Humans have existed (and I suspect lived happy lives) for far longer than planes and cruise ships have traversed the Earth. Certainly humans have eaten meat for as long as there have been humans, but I doubt with the frequency that modern industrial agriculture provides.
It seems like the attitude is basically "now that I know these things are possible, I don't see any reason why they shouldn't be inevitable". But it's possible to do lots of things that fall somewhere inside or outside of this or that person's ethical boundaries, except that we realized there are some things that are deleterious to the wellbeing of humans over time.

I can't tell if it's a refusal to believe that large-scale negative changes that have already begun have an inertia that makes them continue to make things worse, or an inability to conceptualize eventual realities beyond certain time horizons, or else some hardline "I need to satisfy my urges whatever anyone else says" thing... but it's disappointing that folks who get so much benefit from being part of society so vocally and proudly refuse to participate in making a positive contribution to it.

Yes, how could humans possibly enjoy being alive without flights or cruises? There is no way humanity could continue without comforts so intrinsic to the species.
There is no need for those limits, so why impose them?
You mean apart from the massive pollution?
The sum total of aviation and cruise ships is not worth discussing. Getting the world off coal use is much more important.
Aviation is responsible for about 3.5% of climate change, so I think it is significant. Reducing coal use should remain a priority, but I'm sure that industry will find many excuses for not reducing coal.

What concerns me about aviation is that the fuel isn't sufficiently taxed and that empty flights are often made just so that the airlines can keep their airport privileges.

Fuel taxation or slot rules are fair points. Ultimately need to just have carbon neutral fuel for aviation (at prices so that the world continues to get smaller).
Humans found delight and meaning before flight and before cruises. Are you so limited in your capacity?
Why limit humans back to some medieval levels? No need for that.
We don’t really need to do that, there are often more environmentally friendly ways to do similar things
I don't see anyone saying that we should forego medicine and science, or global communication, or even industry--though we should be smarter about what we make and how we distribute it.

But you (and I! I've done this too!) probably don't need to trivially junket through the Med or to have a weekend in Costa Rica to self-actualize. If we want to do it, we should pay for our externalities. A cruise ship's externalities are extremely fucking high, and they're paid for by...nobody, and all of us, at the same time.

"Need" is such a loaded word... let's just find better fuels for cruise ships, let local communities decide if they want them to dock etc. and then people can continue enjoy cruises if they want to.
"Just" find "better fuels" than extremely energy-dense fossil fuels that, when you remove externalities from the equation, are already near a local maximum. D'oh! It's so forehead-slappingly easy! We should just do that!

What you're really saying--whether or not you know it, and I don't know if ignorance or knowledge is worse here--is that we should "just" come back to this in twenty or thirty or a hundred years and in the meantime now we have created a silver-platter excuse to do nothing and continue the outlandishly negative global consequences on everyone for a hypothetical future that you can neither predict nor roadmap.

Here's another one: once energy storage is solved as you posit, maybe then cruise lines should exist. If people want them. Until then, they should be priced with their externalities in and if that kills them (it probably will!) then they failed capitalism, gg no re.

If you want serious discussions and progress on the issues you care about, I would strongly suggest to not lob accusations based on wild interpretations at people.
If you were at all interested in a "serious discussion", you already would've substantiated something, rather than "just invent better fuels" (yes! obviously! but how about today's problems?!) and you wouldn't have retreated to this wispy objection now.
Seriously, where did this conspiracy come from?! I see it everywhere across vastly different swaths of the internet that "the libruls are gonna take your meat." It's always meat.

Like some think tank who wanted to demonize environmentalism just made up this idea that the democrats are gonna force salads on people and it apparently resonated.

It’s amazing how easily people can draw the line from “Politician X once said something critical of Y” to “Everyone in Politician X’s party wants to take away your Y!”
It's because the WEF set have talked about it, along with farming insects, combined with the fashion for veganism.
Some folks have hobbies that don’t externalize 90% of the cleanup cost onto others
If I ever get on an airplane again it'll be too soon, and god willing I'll never have to go on a cruise. (Also I gave up meat over a decade ago and don't miss it)
Good for you. How well do you think that generalizes to other people? Can you imagine people who might have more motivation than you to get on a plane? Who enjoy eating meat and would miss it more than you do? Those reasons might or might not be sufficient for them to continue doing those things, but they exist. Those for whom a thing is easy should perhaps show a bit of normal human sensitivity to the fact that others might find it more difficult.
Cruises are a truly unique intersection of excessive luxury that also generally sucks.
Excessive luxury? Are you serious, any middle class person at least in the west can easily afford a cruise, most only cost few hundred dollars for a few days international trip that has you mostly everything covered with food, lodging etc. I would consider roaming around the world in giant private yacht as luxury if anything.
Middle class people in the west live a life of luxury by most people's standards.
By that reductive standard, everything and nothing are luxuries, depending on the context. Both OPs said “excessive luxury” and the context is: the regions/economies cruise ships generally operate in; western, developed countries.
By that standard, you can say even the working poor in the West live lives of luxury compared to many other countries in the world.
Cruises are by a pure dollar amount one of the cheapest vacations out there which I think is why they're so popular. It costs as much as just the hotel room other places but includes food and all the activities. If you try to go somewhere cheaper like Thailand then it's the flights that get you.
Excessive luxury. Maybe? Not sure exactly what that means. They’re sort of lower class coded. Not the right type of luxury might be a better description.
Make them nuclear. Oh wait, the other kind of environmental activists will prevent that.
I think the strongest version of the activists' case is the economic one, which is something like: the cruise ships benefit the region by bringing tourists and (presumably) paying some direct fees to dock there, but this benefit is lower than the public cost of them belching pollutants into the air, and banning cruise ships is more realistic then passing the more nuanced taxes that would correctly penalize these negative externalities.

The weakest version is the aesthetic classist one that cruise ships are tacky. I have the same opinion, but convincing people that the thing they like is lame doesn't seem like a great tactic.

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Agree. Italy has in the past deployed the military to keep cruise ships and their tourists out of Venice. Because even if you deny them from docking there, they'll just dock somewhere close by and charter a bus. Lots of 1-day-tourists means lots of dirt and trash and dangerously crowded roads in and out of the city. And since most cruise ships are all-inclusive, those tourists pretty much won't buy anything. They stay exactly 1 night at each location, so they cannot even afford to buy a meaningful souvenir because then they won't have budget left for souvenirs at the next 10 stops.

So yes, "cruise ship tourists ruin the economy" is probably the best argument for getting the locals on your side.

What's the pollutant cost of flying the equivalent number of tourists there? I would have thought, naively, that boats are way more efficient than jet engines, even after hauling casinos and swimming pools along for the ride.

I wonder if "don't run your power plants when docked, buy local electricity instead" is a reasonable rule.

I too think cruise ships are tacky, but when I examine that reaction I find it really hard to justify. I think it might just be a classist thing on my part.

I doubted the claims around here, so I tried to get some numbers from a DDG search.

I didn't find anything definitive, but looks like cruise ships spend something on the order of 100kg of fuel per passenger-day. This is completely out of line from any kind of transportation (with speeds on the order of 40km/h).

Their main issues are that they use a huge amount of electricity, and that they run way too fast for a ship.

Thanks for finding that. So we're talking about 100 passenger/km for 12 litres of fuel (very roughly). That's.... 10-20% worse than an SUV with a single occupant? Double a fuel-efficient car? And apparently 3-4x a commercial jet.

With all the other problems people have mentioned, I can see why air passengers would be far more desirable from the destination's point of view.

The "on the order of" on my comment is load-bearing.

I've found a lot of things from 400 l/pass*day to 100 l/pass*day, and 20 km/h to 40 km/h.

The higher speeds tend to come with the highest fuel consumption. But I couldn't find good info on the correlation between them. So, they probably consume a few times more fuel than a SUV, and closer to 10 times more than a jet, but I can't get you any precision at all.

From the featured article:

> Another study released in April by the US environmental group Friends of the Earth found that passengers on a typical cruise ship each emit roughly 421 kg of carbon dioxide a day—more than one does on a typical one-way flight from New York to Los Angeles.

> banning cruise ships is more realistic then passing the more nuanced taxes that would correctly penalize these negative externalities.

This seems like it can't be true. Banning cruise ships in a port or region seems exactly as easy as taxing them some big quantity for fuel burnt for the entire cruise.

Fair, I don't actually know which legislative method is easier. I have a vague hunch that a city is more likely to be able to dictate who docks at their ports than introduce their own pollution taxes, but I don't know.
I'd expect that they tend to extract a lot of concessions, especially from the lower-tier stops.

* Were the quaint little towns, the ones adjacent to a natural feature, the fishing villages or historically relevant cities, ready to support a million-tonne liner with huge clearance requirements, even aside from any first-order pollution needs? Who's paying to build and maintain facilities, and when the programme changes and the service is abandoned, who cleans it up afterwards?

By comparison, cargo ships tend to dock at more purpose-built facilities "elsewhere"-- points specifically chosen for their capacity, but you can't really tell tourists "we're docking here, and taking a four-hour bus ride to the actual attraction city?"

* How badly does the town get coupled to the tourist economy? Will you end up with 82 trinket shops but no local grocer? Cruise tourists tend to be much more "captive" than most self-directed modern tourists-- so it can turn into a game of kickbacks to ensure that that the tour itineraries and maps showcase your business instead of your competitor, draining profits from the local community.

Aside from that, a damning factor of cruises-- and to a lesser degree international ships in general-- is the tendency towards "flags of convenience." It screams that the business isn't viable if they're held to first-world labour, operational, and environmental standards, and it means it will be virtually impossible to corral them for things like "you have to be carbon-neutral" short of raising huge international fracases and closing ports.

This’ll go about as well as trying to get rid of Golf courses on similar environmental grounds
> “Cruises don’t serve any purpose,” she said as the morning sun filtered through her kitchen windows, hinting at another sweltering August afternoon. “The container ships and the ferries benefit everyone, but the cruises are benefiting the shipowners and then the people who save up to afford a cruise. It’s entertainment, and it’s entertainment that’s filled with completely ridiculous things, like an ice-skating rink on a ship. I mean, how can we authorize that?”

That's kind of an odd perspective. Lots of things humans do don't "serve any purpose" other than entertainment. Get rid of movie theaters?

The cruise industry deserves a lot of criticism and should probably get some regulation. Coming at this from a perspective of "I don't find cruises interesting so let's get rid of them" them does not, to me, sound like a good strategy. Personally, I have been on one cruise and I really enjoyed it. The price was really good and I'd even do another cruise at a higher price if that was the impact. I enjoyed being on a very nice hotel that I could wake up in a new place each day.

I don’t think we should get rid of cruises, but I don’t see the movie theater comparison as valid. Movie theaters don’t emit tons of CO2. (One could also make the argument that movie theaters propagate the arts, which is a good purpose)
> Movie theaters don’t emit tons of CO2

Perhaps not directly, but in most of the USA, everyone in one drove a car there. The energy use from those same people streaming the movie at home would emit much less.

I'm not for a ban on any of those, but very few activities are truly carbon neutral.

I think it's a matter of scope. Cruise ships are unusually polluting. This is why folks argue to ban private jets and not commercial aviation. Or in this case, cruise and not container ships.
A lot more people get "value" from Fox News vs. HN; ban the latter to save resources and those people can go do some productive with the time they're currently wasting.
Again: That's not a helpful comparison. Cruise ships have absolutely ridiculous emissions. HN does not.
This makes sense to me as an argument. People downvoting this because they disagree is pretty sad.
Everyone drove a car to the theater to sit sedentary for 3+ hours and eat garbage food before driving home. Lots of societal bad there; why do you get to decide?
Things you listed are parts of Murican way of life, not a part of cinema experience. Ppl around the world mostly use bikes or public transit or at least taxi to go to the cinema. In my local cinema they serve nice salads beside traditional pop-corn.
You have to look at the whole picture. The people who drive to the theater emit CO2. Same for car racing. I bet the emissions caused by the race cars are dwarfed by the emissions of people driving to any larger music concert.
Most movie theatres propagate nonsense superhero stories. Lots of CO2 emitted in the creation of those. I guess we should delete movie theatres along with everything else.

The problem with all such arguments as they are fundamentally nihilistic in the final analysis.

If CO2 is the concern then include the CO2 in the price via a CO2 tax (or a per person CO2 budget if you want something objectively worse but more intuitive, then people can save up their CO2 credits for a cruise if they really want a once in a lifetime thing).
I’ve never been on a cruise and I don’t ever particularly want to go, but these activists sound like a bunch of miserable bastards who hate fun.
My take away was also bitterness and jealousy, the arguments just don't really add up to banning cruises.
I've been on a few cruises, they're fun and certainly an amazing feat of engineering but a bit of reflection and you realize perhaps moving the equivalent of a self-contained resort from place to place just so that people won't be a bit bored when in-between ports might be a bit egregious in the scheme of things. Do people really need to experience up-scale restaurants, casinos, roller coasters, zip-lines, skating rinks, musicals, comedy shows, etc while at sea? Combine that with the cruise industries' general poor track record of worker mistreatment, at the very least some much heavier regulation seems warranted. I'm guessing eventually cruises will go the way of orca shows in popularity.
The problem with this type of argument is it always circles back. For example, what is the purpose of the 58 year old painters art? Hmmm, it doesn't seem like the painter is serving any purpose.

The crux of the argument is, there is no such thing as an objective purpose. Nothing in the universe has such a property in the final analysis. Thus purpose must be defined by individuals.

Everyone thinks the things they don't personally enjoy or benefit from are the ripest targets for regulation (if not outright elimination). Just like everyone thinks that their (or quite often their parents') choices of where to live and how to get around should be easy for everyone else to adopt. Sometimes those preferences happen to be consistent with environmental or other concerns, but that's rarely the real motivation. People just like to look down on other people. The difference is apparent when you consider that the "activists" have generally not thought for one minute about what it would really take to make their prescription real, or what secondary costs (including environmental ones) that would incur.
The interviewed activist is a painter. I would put painting and cruising in same bucket of utility. And that both have value because they provide happiness.
Not everyone thinks that. Come now. I and many other people can honestly say we never woke up in the morning filled with zeal to ban out regulate someone else's entertainment.
Most people lack a generalised sense of empathy. They can empathise with people who are missing out on things they (the observers) also would want but don't really care if someone is missing something they (the observers) don't care for.

Applies equally well to parks, pets, porn, cars, cycleroutes, childcare...

> "I mean, how can we authorize that?”

Wow, she's saying the quiet part out loud. No, we don't need her goddamn permission if we want to ice skate in a boat. That sounds awesome.

Agreed. At what price do you think cruises internalize the externalized costs?
Im curious why cities don't try to capture more of the value?

- Impose massive docking fees, cheaper cruises need to anchor far away and ferry in.

- Force passengers to buy vouchers that can only be used in that city on that date.

If they impose too high prices the ships go elsewhere, either a different city or they buy their own land and build their own port on it. While those options don't always exist, they are real enough that most cities dare not push to hard.
This still seems solvable; environmental regulations are almost always stricter at higher levels of government, and charter buses and massive development need to meet those.
Cruise ships stop at different countries as well, if your gets too bad they go next door. There are a number of islands in the Caribbean that don't get much ships. The Mediterranean likewise has a number of countries to go to.

You could prevent Alaska and Norway cruises, and a bunch of others that are mostly one country, but there are lots of other countries for those ships to go to.

But if the people in the article get their way then there would be no cruise ships at all?
I too find cruise ship pollution while in port annoying, especially so once you realize they're burning oil to run generators ... while being just meters away from a perfectly working power grid.

It seems to me that a perfectly reasonable solution that would satisfy all parties would be to mandate that EU ports have appropriate grid connections, and that cruise ships must make use of them.

Or impose lots of stricter rules on all ships in ports. Cruise ships will follow them to get the customers; container ships to get at the consumer markets.
The difference is that other ship types don't have an incentive to run their engines once they're docked.

Cruise ships as floating hotels have high power requirements even when they're not underway.

They're also likely to be docked at "the marina", or another downtown or residential area. Container ships will typically dock at transport harbors, which are in industrial areas outside of population centers.

Cruise ships are car-free walkable cities. Activists should love them.
This is actually a good point. What about all the pollution that is NOT happening because those thousands of people are on a cruise for the week? Probably taking flights somewhere, yes? And driving cars. All externalities should be compared against the alternative.
These are great points but I do think this article is primarily about local NOx, not global CO2.
This is HN we like to look for and present the data here:

> the world’s largest and most efficient cruise ships emit about 250 gCO2/pax-km.[1]

> The average passenger vehicle emits about 400 grams of CO2 per mile [250 gCO2/km].[2]

So a cruise ship running almost continuously emits about the same per passenger as the average car. The average car however does not run continuously and often has more than one person in it.

So for the cruise ships to actually prevent emissions, the people that are in the cruise ships need to have otherwise been continuously driving alone in their cars at around 40 km/hour (25 mph) 24 hours a day for the 1-6 weeks they spend on the cruise. I highly doubt their daily lives pollute this much—even given their average wealth.

1: https://theicct.org/marine-cruising-flying-may22/

2: https://www.epa.gov/greenvehicles/greenhouse-gas-emissions-t...

Thank you. But what if you factor in a flight? This assumes you need to travel to your vacation destination of course. That's additional miles travelled in an aircraft at 31 gCO2/km, would be 1000s of km that you don't need to factor in for a cruise.
I didn’t, but quite many people actually fly to and from the the cruise’s start harbor and destination. Medium haul passenger flights tend to by around 180-200 g CO2 per passenger km, so (surprising to many) less then a single occupant car. If your cruise passenger would instead fly to every single of the cruise’s stop, they can actually expect to emit less.

However this kind of detailed analysis is out of scope for me personally. I don’t have the means to do excessive research factoring in various alternatives (and if I did I—as a non-expert—I would risk overfitting). For example a tourist arriving on an airplane is likely to stay in a hotel connected to the electricity grid, which is more likely to be fare more efficient and less carbon intensive than a cruise ship generating the onboard power with heavy fuel oil.

I can, on the other hand, do a rudimentary ‘sniff test’ and locate easy to find data for what is going to be the biggest—perhaps even the overwhelming—factor, the emissions of the transport it self. And as such the claim that: “[we should consider] all the pollution that NOT happening because those thousands of people are on a cruise for the week” miserably fails. Looking into the emissions of an average cruise ship tells us the story that—to the contrary—we need NOT consider this.

Ok fair enough. If we stipulate that, then we just need to regulate these emissions because they are getting a free ride on externalities. We just need to say 'if you wish to dock at our port, you must have a boat that emits less than x'. The market will then adjust by building ships that are cleaner. Cost of a cruise will go up by a few bucks, problem solved.
Large ships burn the worst fuels its very difficult to regulate the industry towards any kind of emission standards I think in recent years some large countries have strong armed the adoption of lower sulfur fuels or something but outside of territorial waters I’m sure these cruises burn the grossest by products of the petrochemical industry there’s no economic reason not to

On those grounds alone I sympathize with folks who don’t want to watch these things lumber into their port as people have pointed out they’re doing precious little for the local economy anyways

This seems very French, and also very irrational.

Show me some causative data that the cruises cause these problems, and they might have an argument other than "I seem to be having more trouble breathing"

Disclaimer: Fan of cruises (and not initially, but Harmony of the Seas changed me somehow)

I agree, cruise ships pollute a lot, are wasteful, and benefit very few people, but rely on public infrastructure. We'd be better off without them.