My goodness, get a clue. So, taking this a step further what we should do is forget about using any of our national power to protect ourselves and not have a border at all. This way anyone who wants to come into the US can come in willy nilly. Of course, in a fit of euphoric frenzy the rest of the world will see the benevolence of our actions and they too will take down all borders. And since we do that everyone who is a bad guy, whether it be a member of ISIS or MS-13, will disarm and hug his neighbor, tears of joy streaming down their faces now that the evil US has learned that borders are bad things.
Or, maybe he should do some research and realize that we do indeed have customs officials in many nations. They work out of our Embassies. And amazingly, other countries do the same thing here. We call that reciprocity. But, since we happen to be the richest nation in the history of the world, we can send a bit more than say, Lichtenstein. But if he did something like that then he wouldn't be able to bash the US and bash President Trump, even though we've been doing this since say… 1970 or so.