The conservatives who hyperventilated about the Democrats’ explosion of identity politics seemed to forget that Mr. Romney also dragged Rev. Martin Luther King Jr. into this campaign — claiming that he “saw” his father, a civil-rights minded governor of Michigan, march with King in the 1960s. The point of Mitt Romney’s invocation of the race card was to inoculate himself against legitimate charges of racial insensitivity; he had never spoken out about his own church’s discrimination against blacks, which didn’t end until 1978. Instead, the tactic ended up backfiring. Late last month The Boston Phoenix exposed this touching anecdote as a fraud. George Romney and King never marched together.