Stephen Colbert Does The Real Math On Donald Trump's Promised Border Wall

President Donald Trump has promised so many things of his controversial southern border wall. On the 2016 presidential election campaign trail, Trump vowed that his proposed U.S.-Mexico barrier would be “big, “powerful,” “impenetrable,” “physical” and “beautiful.” With the due date for contractors to submit prototypes falling Friday, “Late Show” hostStephen Colbert talked to construction experts to find out just what it would take to build the barrier ― if all Trump’s p...