Right, so how would you feel about Mexico protecting Mexicans in an area that is historically Mexican?
If they needed protection, I'd accept that. It is one of the problems with the invasion of the US. Huge swaths of the country have not assimilated to the US.
I'd say that if you don't want that to happen, you're totally in sync with putting US troops on the US southern border and sending home invaders into this country for good.