The Wall Street Journal POTOMAC WATCH September 13, 2012, 7:10 p.m. ET Mr. Romney, Trust Your Pants Obama tells Americans the terrible things the Republican will do to them. The Republican remains silent about what he would do. By KIMBERLEY A. STRASSEL In the classic 1968 film "Once Upon a Time in the West," a villainous Henry Fonda shoots one of his lackeys, in part for the sin of wearing both a belt and suspenders. How do you trust a man, muses Fonda, who "can't even trust his own pants?" Mitt Romney is slipping in the polls because, when it...