Breeding out takes too long. What massive immigration does is crowding out.
They are not going to crowd out anyone, once they have enough people they will KILL anyone not like them. It is only in Western European civilizations that mankind began treating other races as equal. In the rest of the world, everyone hates anyone that is not THEM.
It serves 2 purposes..The dems can get rid of the black vote,won`t need it anymore and the Mexicans work,which means dems get tax money from them...Unlike the black democrat voters who need parenting till they die...