Either way, it takes time to produce the vacine-enough of it to protect all of us...and once treated we are immune for up to 10 years...so why not go ahead and get it in place like we would any other system of defense?
To me, it sounds like a reasonable precaution that gives terrorists one less weapon to use against us.
I just hope they distribute tin hats along with it...that way i can be protected from all threats-those real and also those perceived...