[s5300]

Getting into the realm of Reddit tier comments in replying to this...

But in a genuine attempt to clear you up -

The people who made Nazi Germany a thing were "just citizens of Germany supporting the policy of the German government."

Institutions, such as YC, typically tend to have a set of morals/guidelines that they follow (and usually clearly state)

If it so happens that a policy of the US government goes against said morals/guidelines and you're in support of them... as what most see as a pretty important part of being in the US, they're free to give you the boot from their institution.

If they who be booted perceive their bootening as something that is illegal, they're also free to sue. Whether or not that lawsuit is credible/goes anywhere is up to a judiciary.