You don't worry about throwing all of the invaders out; you do it one at a time. You fine and jail employers of them. You let US citizens who could be doing the jobs they do sue their employers for lost wages.
These are not "illegals", which implies they can be made legal. They are an invasion force which undermines the protections of the US worker, our environment, our culture, and the value of citizenship. But, hey, they're really good for corporate profit.