We need more than a wall

A reader writes:

In all the hullabaloo about the wall, I don't know why no one has pointed out that only a minority of immigrants are "wetbacks" in the traditional sense. [About 40%] are those who come on visas and simply never go back. Immigration makes no effort to search for them. Border cities permit crossings for shopping and sightseeing with no documents at all typically being requested. Those from more than 50 miles into the interior may obtain automatic three day weekend shopping visas. Longer visas can be easily obtained. Those who never go back are in no case ever searched or are required to account for themselves or their whereabouts.

My published articles are archived at iSteve.com -- Steve Sailer