Now, if you are looking at those numbers and thinking,”where the heck did those very specific figures come from?”— congratulations, you are rational human being. Those totals are, of course, clearly either made up from whole cloth or, at best, vastly overstated. Most estimates of the undocumented put the figure in the neighborhood of 11 million to 12 million, including those produced by Mr. Trump’s own DHS. Cost estimates vary widely, but even the most pessimistic — from the Federation for American Immigration Reform — pegs the cost much lower than (or about half) the president’s estimate of $220 billion annually. So what’s the source? Administration officials have offered no explanation, and that includes Mick Mulvaney, Mr. Trump’s acting chief of staff.