If you were to randomly ask a sample of 100 Americans from around the country why the mortgage interest deduction was implemented in the tax code, I'd wager that the bulk of the answers would range from "I don't know" to "they were designed to give a tax break to the rich." Both answers suggest ignorance of facts, but the former is at least honest. The latter is just regurgitation of a leftist talking point by those feigning knowledge on the subject. The truth is a bit different than popular perception on this matter. Few, if any, among that small...