Weeding out people who have opposing political viewpoints to the party in power but pose no threat is a dangerous idea that doesn’t speak to our nation’s stated principles.

Sure. I agree. But without evidence, that doesn't sound like what they're actually doing. Sounds like to me they're weeding out people that may have ill intentions when visiting. Which of course would skew to the party not in power, since they're more likely to be the ones making death threats to the other side. Which might I add is not protected speech no matter if you're a citizen or not. It's assault.

All systems of control are not bad, as long as they are not abused. But as we know, they are always abused

Right and you have a ride to privacy and we have tools to make that happen. You can't just say stuff on public platforms and expect that anybody will let you do anything they want based on what they may have read there.

What you say in public is something that you can control. It's just like face tattoos. No there's nothing bad or morally wrong about face tattoos but you don't get to decide how other people feel about it when you go apply for jobs.