A good start but should be along the entire water border, then concertina wire on the shore. Dry border should have a wall. Everywhere should be armed troops to shoot any military age people that still manage to cross.
Honestly, to stop this invasion, the US needs to invade Mexico, and take over the border for about5 miles inland. That would become American soil, and you would build the Customs and border wall there.
And just who is going to Stop us???