God turns people away from heaven for being ungodly and bad people. Why can't we turn away rapists and murderers from our border?

Because that would be... Emulating God? The Bible explicitly says that God has to choose who is virtuous and who isn't. Besides, the majority of people jumping the border aren't criminals.

Having a strong border [...] are all heavily tied to Christianity and Theology in general.

Christianity is a universal religion. It means that every human on the planet can and should become Christian. Jesus doesn't do any distinction by nationality. Nations don't even exist for Christianity.

The verse referred to is teaching not to be quick to anger and to not act purely on emotion, a decidedly liberal trait if I may add.

But where else does Jesus tell you that you're allowed self defense? If the command is "not kill" then if a thug enters my house and starts beating up my family I have absolutely no religious justification for shooting him.

king David a man after God's own heart (Acts 13:22) killed tens of thousands of people (1 Samuel 29:5) in defense of his loved ones and his country. Not to mention the entire Zionist movement throughout the Bible.

Yes, but I'm not a Jew. I'm not the chosen people. That passage shows that Jews have the right to kill everyone else. It doesn't tell me anything about how me, non-Jew, have a right to defend myself (individually or collectively).

I find it absolutely ridiculous that non-Jews believe in a religion that starts with Jews being the chosen people. If this is not cuckoldry, I don't know what is.