Can Twitter Be Made in China? (newyorker.com)

For a foreign company attempting to break into that market:

Not with censors, minders, and the party looking over their shoulder. Also, would you care to give half your company over to the authorities.

For a home-grown company attempting to break out of that market:

The same as above applies, but in reverse. You need to get rid of that albatross around your neck.