We weren't talking about mandates, but I'll bite. The difference is you don't have to trust the government to know seat belts save lives; the law on seat belts is common sense to anyone of sound mind. On the other hand, show me anyone who can see that getting an injection of some vaccine of unknown (to the average recipient) content and function is common sense. Note that I'm NOT making ANY claims about the vaccine efficacy or danger of lack thereof, simply that a typical individual can't look at the clear liquid in the syringe and innately know that it saves lives. It necessarily requires faith in government or medical institutions or doctors who tell us they are safe. Seat belts don't require such faith, so such mandates can't be compared like for like.