"On the other, how much pressure is reasonable to put on parents to vaccinate their children against an illness that poses less danger to them than meteors."

Not sure about the statistic, but it's irrelevant; the reason polio is not acommon that is because... Wait for it... We all get immunized! If we just stop getting the immunization and a strain comes in from over seas (which it does, even today), well, it's a problem again.

You speak of a debate as if each side is on equal footing, but that's not the case. This is a debate of fact vs ignorance. These people put everyone else at risk, my children as well as your own. I have little patience for that dangerous sort of ignorance, and I'm ok with harsh language.