Saying they "have every right to" means nothing. Obviously if you make the laws you have every right. The question is: is it humane? Is it smart? What position do you want to have in the world? Do you want to be an isolationist ethnostate that has very limited trade partners?

Have you considered that it's possibly not smart economically to treat people from neighbouring countries inhumanely, especially if they're your biggest trading partner, net migration from that country is negative and the migrants that do come from that country are a massive net positive for the economy and commit crime at a lower rate than natural born citizens? What is the point then of torturing and killing these people simply for crossing a border?

It is not economical, in fact I'd be surprised if it isn't disastrous for the economy. It has nothing to do with crime. It's not because of religion, not that that wouldn't be a bullshit reason, but the vast majority of mexicans are christians.

Everything makes sense if you look at Trumps trajectory from refusing to rent apartments to black people, to purchasing an op-ed against the central park five, and afaik to this day defending his actions saying "they must have done something," Insisting that Obama is a nigerian muslim and therefore an illegitimate president, signing a "muslim ban" for no other reason than to ban people based on faith... all the way to concentration camps for brown babies.

You can either jump through hoops to say correlation is not causation for every single one of those, or you can accept that he's a fat racist retard who's so incredibly dumb that he can barely speak his own language.