Israel has said their wall has been very effective.  Where the wall is on the border has also been very effective. Hawaii is very protected by the "wall" of the Pacific Ocean, so there is no local experience of living on the border. It is very easy to get the money from Mexico to pay for the wall. A dollar a barrel of oil pays for the wall. Three and most important, the only egg on the wall is the egg laid by the  Democrats putting up such a flawed candidate for President.