well, I can't really say what I would do in the event of a Patriot Act-type mandate, if there were truly an outbreak of something like smallpox. It wouldn't be very realistic to think I could leave the country in that situation, there would probably be military enforcing a quarantine, and I certainly wouldn't want to be responsible for spreading a disease to a previously unaffected area.
in reality, if soldiers or other law enforcement-types showed up at my house with guns during a major bioterror attack of smallpox and said "vax or else" I'm thinking I'd go along with it, because I'm not that trusting of the government about what the "or else" would be. I'm not going to traumatize my kid even more, in that situation, she's going to end up vaxed anyways. I might try to falsify the vax, like with smallpox, I might try to make it look like we'd already had it (some type of mark on your arm, right?) If there were a choice, like MMR or quarantine, I'd comply with quarantine.