The wall is to help both Mexico and the U.S. In fact, Hillary Clinton, Barak Obama, Chuck Schumer and 23 other prominent democrats were in favor of a fence along the border in 2006. Also in 2006 the Mexican president sent out their national guard to physically stop illegal immigrants crossing the border. The reason some sort of wall in beneficial is because the drug cartels grow their drugs in Mexico, then sell them in the states and buy our affordable American guns, return to Mexico and are able to overpower law enforcement many times. In 2006 when both countries were strict on illegal immigration the drug cartels were being put under control. But later on both countries got left wing presidents who were easy on them and thus here we are.