The problem is - wearing a mask yourself isn't as efficient as everyone around you wearing it. "I worry about my health, so I wear a mask, it will protect me" is not how it works. How it does is - "I worry about everyone's health, so I wear a mask, so even if I'm sick, I at least protect others"
Now, I'm sure you understand that the second point of view has to be enforced on your dumbass fellow Americans, because there's way to many people who just think, fuck it, if I'm sick, at least I'm gonna spread it to everyone else. Speed limit infringes upon your freedom, so you don't kill people. Stopping you from spreading your germs around works on the same principle