As the saying goes, “Fences make good neighbors.”
And you are very correct, fences make great neighbors. The US is being overrun by refugees actually. All the talk about how they are coming here for a better life, well obviously. But look how other countries deal with refugees. It could be said Mexico and several Central American countries are involved in civil wars with drug lords, etc.
So they are refugees escaping a war. What are other countries doing when they are bordered by countries at war. They certainly do not let them just come on in and do as they please.