With the Republican presidential nomination almost in his grasp, Mitt Romney rolled out a notable endorsement last week, from a former governor of Florida. It was notable not because it's likely to change the mind of any voter, but because it required the Romney campaign to utter a four-letter word it has been loath to use: Bush.The presidential candidates never tire of reminding us theirs is the party of Ronald Reagan and Abraham Lincoln. That the modern version is, more than anything else, the party of Bush is something they prefer to omit.The last two Republican presidents were members of...