Donald Trump’s proclamation that he would build a “wall” along the U.S.-Mexico border was a major selling point in his campaign ... It was this commitment that helped propel Trump to the forefront of a crowded field of primary opponents ... and it no less helped distinguish him significantly from Hillary Clinton ... nationwide. It will soon be show-time for Trump, ... millions of Americans are eager to see him follow through on this promise—... There is some angst, that Trump and .. advisers might be taking a step back from ... a wall ... instead considering a virtual barrier,...