If and when Barack Obama wins another four years in the White House, one of the first people he should invite over is Rick Santorum. That's because when the scholars chronicle the history of his 2012 race, it will be Mr. Santorum who will get credit for handing the victory to the Democrats. And if you don't believe it, just ask Mitt Romney. Without his buddy Santorum in the contest, Mr. Romney could have taken a more moderate path to the nomination and would not have been dragged so far to the right in order to compete for the ultra-conservatives...