Just a week ago, Mitt Romney and John McCain barely seemed capable of uttering each other's name.
Now we know that, like so many people embroiled in conflict, all they really needed was a little space. Where just a few days ago McCain was a spineless moderate in Romney's reasoning, by yesterday he had become a war hero and the right leader for these tough times.
The rehabilitation went both ways. Those sarcastic comments McCain made about Romney being "the true candidate of change"? All is forgiven.
Cynics will say Romney has changed his position yet again. But if there is one area where he has shown great consistency, it is in his willingness to change. Compared to his shifting views on abortion, stem cell research, gun control, and gay rights, embracing John McCain is minor.
Some analysts immediately concluded that Romney's endorsement would help McCain with conservatives. Because McCain has on occasion voted against a tax cut and favored a path to citizenship for illegal immigrants, his credentials as a "true conservative" are in disrepair.
Of course, conservatives weren't especially high on Romney as the standard-bearer, either. He was at his most conservative - also, at his scariest - when he exited the race last week amid dire predictions that the Democrats would drive America right into the second tier of nations. If he thought John McCain was the solution, it didn't occur to him to mention that.
For a man who is amassing so much experience with reinventing himself, Romney is still having difficulty managing his costume changes gracefully. Partly that's because they come with so little warning.
The Mitt Romney who ran for the Senate in 1994 might well have made a better presidential candidate than the 2007 model. But that was before he morphed into an antiabortion, anti-gun-control conservative. When that strategy wasn't working, he became the man who told us, "Washington is broken," and invoked Ronald Reagan so often you would have thought he was conducting tours at the Reagan Library. Oddly enough, he never seemed to think that one of things that is broken in Washington might be the administration of his good friend, George W. Bush.
Romney and McCain make a truly odd couple, and McCain for one seems to know it. His disdain for Romney was palpable every time they were forced to share a stage. McCain will take the endorsement, but don't expect them to be spending a lot of time together.
Romney does deserve credit for one thing: The man is forward-looking. Dropping out of the race in the name of party unity was good for his future prospects, and so is jumping headlong into the McCain camp. If McCain loses, Romney's next campaign for president could start as early as next year. And even if the 71-year-old McCain wins, a run in 2012 might be possible.
I used to wonder what Romney really thought about his frequent changes of heart. But I really don't think he gives them much thought. He is a born pragmatist, a problem-solver, a salesman. His product, in this case, happens to be himself. If it isn't what the customers want, you tweak it until they like it. Isn't that what Detroit was famous for, back in the days when George Romney was running American Motors? If bashing McCain doesn't work, Romney is flexible enough to shift gears.
Still, it seems that one of the lessons of Romney's failed presidential bid is that mere expediency won't get you to the White House. He lost to McCain primarily because voters trusted McCain's authenticity. That lesson, alas, remains unlearned.
There were indications yesterday that McCain and Romney plan to do a significant amount of traveling and campaigning together. I'll believe that when I see it.
They are, in fact, headed in opposite directions, and Romney, still pitching, still selling, doesn't seem to understand why.
Adrian Walker is a Globe columnist. He can be reached at walker@globe.com.
