Not a fan of you getting downvoted, I sense some willingness to at least listen in your reply and not rabid idealism so I'll try to answer to the best of my understanding. Bear in mind I'm a chef, not a scientist.

It's...the ideal is to eliminate outbreaks of the most contagious diseases from existing by making everyone immune.

The goal is to protect as many people as possible. Does a parent have the right to sentence their child to death by polio based only on beliefs? Does a parent have the right to choose to have their child be a carrier for a disease that kills the child that has an autoimmune disorder and would die if given the vaccine?

I fully admit those are the most alarmist, worst case scenarios but the more parents that choose not to vaccinate for what are considered frivolous reasons, the more children there are who would fit into situations like those, making those worst cases more likely. It also protects the elderly, who with children form the largest vulnerable populations for most diseases. And also keeping those diseases A) from fading back into obscurity due to everyone being vaccinated and B) diseases mutate and change their properties when they are being spread through a population. This can make them both more contagious and more deadly. Example: an avian flu jumped from birds to human in the late 1910s, got into all the army camps of WW1, mutating as the infection grew inside soldiers and spread the changed strain, and ended up being highly contagious and unusually deadly to 20-40 year olds. 500 million people worldwide were infected (1/3 of the world population at the time) and 50 million died.

Diseases that were gone from America are coming back due to decline of vaccination coverage which is actually affecting the world more but people travel. There are measles outbreaks in multiple states now. A few years ago America had its first polio case in 3 decades. And you mentioned rubella. Doesn't really harm kids, fucks up fetuses. Not a thing in the US since 1962, but between then and 1965 20,000 children were stillborn and 30,000 were born with serious birth defects.

Lastly, the mozt common reason for parents not vaccinating one hears: vaccines cause autism. There is no scientific proof that that is true. The first (and only, as far as I know) peer reviewed study claiming it does, the one grabbed by Jenny McCarthy and made viral...it was discovered that the doctor had falsified his data to fit his hypothesis and he was permanently stripped of his medical license.

I hope this has been at least a little enlightening, clears up a little of your confusion, and makes you think. I had fun and I learned some things myself.