If Trump was serious about security he would have 15,000 fully armed troops on the border with orders to shoot if threatened. Kill any armed illegals crossing the border with one warning shot first and then hell fire.
Part of the problem is determining exactly where the border is.
Some places it’s well defined and others it isn’t. That’s why
a wall, fence, or some other defining line is needed.
It’s kinda like you own some property without a fence, etc.
People can come on it intentionally or not.