Even if Mitt Romney wins in Florida on Tuesday, he still may lose the presidency come November. The old adage of “divide and conquer” may work well in war, but in politics it’s not always a smart strategy, especially in Republican primaries. Ronald Reagan’s name has been evoked quite often in this race. The Gipper must be turning over in his grave that Mitt Romney has so badly violated his 11th Commandment: “Thou shalt not speak ill of any fellow Republican.” Reagan’s law not only sounds great, it’s smart politics. Reagan understood that the very same Republicans a candidate attacks...