Barack Obama ran for president as a centrist, as someone who would rise above partisan divisions and make Washington work.

That may well have been his sincere dream — to lead key people in both parties to some grand synthesis of liberal and conservative. I thought that at least he would try.

In 2009, the GOP was a spent force. The erratic candidacy of John McCain left the party fractured and leaderless, vulnerable to a young president swept into office in part by the nation’s yearning to put its racial sins in the past. Obama had a decisive victory, tremendous support and vast good will.

What seems clear now is that he lacked the temperament and the strategic flexibility required for success. He lacked the vision to recognize and seize unexpected opportunities.

All he had to do was borrow a Republican idea here and there at the right moment. Had he been clever about it, he would have crippled his opposition. It’s not hard to imagine LBJ or Bill Clinton ruthlessly moving the chessmen, dominating more and more of the center, isolating the far right, peeling off moderates.

But backed by Democratic majorities in the House and Senate, Obama surrendered to hubris. He behaved as if he were invincible. He slapped down Republican objections with his “you lost, we won” jibe. He rammed through massive pieces of legislation with little or no GOP support.

By the summer of 2010, Gallup had tagged Obama as one of the most polarizing in history — with 88 percent approval from Democrats but only 23 percent from Republicans.

Looking back, it seems that Obama drew from one well of his personality for the campaign, and tapped another — one more gloomy and narrow — when confronted with the pressure of governing. In any case, a different Obama emerged.

We are nearly through his first term, and he has shown little ability or willingness to deal realistically with the nation’s mounting problems. His trillion-dollar budgets were laughed out of the Senate. He has no real plan for entitlement reform.

Some believe that if re-elected, Obama — freed from the need to keep his base intact — would at last tack to the center and fulfill the promise of ’08. It’s possible. If he wins Tuesday, I hope that it’s so. I hope he draws from the Obama we saw four years ago.

But I think the likelihood is low. Barack Obama had his chance. It’s time to hire someone else.

Mitt Romney is distrusted by many on the GOP’s right as an inveterate flip-flopper. But to move this country off dead center, any president will have to compromise. There will be times he will have to anger people in his own camp.

Romney has shown in the past, in his record as Massachusetts governor, a capacity to work with the opposition and do what’s needed to accelerate economic growth, tame our out-of-control entitlement programs, bring down the budget deficit and reform the tax system.

The nation’s problems are so deep that even with the best of luck, a Romney administration isn’t likely to offer profound change and transformation. But that’s not what’s needed. What’s needed is to turn the ship, so that the problems we face stop festering or getting worse and start improving. It would give the nation a burst of confidence just to see that our most difficult challenges are being confronted rather than ignored.