Great post!
For sure politicians have long used fear based language. Both sides do.
About vaccines, I have a very educated friend who refuses to believe that vaccines and flu shots are safe. She also believes that fluoridated and chlorinated water are poisonous. Presenting with the science of it doesn't work to change her mind.
This reminds me of the stance against nuclear energy which is clean energy. This fear came about because of the Three Mile Island partial meltdown in '79. Even though no one was killed, no radiation sickness has been reported and the radiation was contained in one reactor. I think the clean-up was finished in '94.
But some think "Nuclear", they might think bomb or Three Mile Island.
It's truly hard to get past ingrained fear, no matter what the facts are.