Dev.to Ethical Hacker\Security Engineer

Currently, I work as a software developer and I really do like it. At the same time I often think about becoming a cop or going into the military. I think about this alot because I have a passion to help and defend people that can not do it themselves. My latest thought is why not go into system security? First of all it is much more safe then the other options. I feel that such a move will help me feel like I'm contributing more to society and making a difference for the good from a techie standpoint without completely leaving tech. I really want to do something with my life that will help my fellow man and citizen not just make app software that will outdate in 5 years. So at this point I'm thinking about leveraging my knowledge base toward a sys. security engineer. I was wondering if there are any ideas out there in how one becomes a corporate security engineer? What type of degree? What type of experience? Right now I'm taking the Stanford Cryptography class for fun. Any wisdom someone can throw me? Thanks..