You know how I feel about seeing all the living presidents together. Their rare gatherings together say more to the world about our democracy than any history lesson ever could. But there’s something especially rich and sentimental about this photo from the opening of George W. Bush’s library and museum that popped up in my Twitter feed this morning. In the presidents’ club all is forgiven, it seems.

Presidents Carter, Clinton, Obama and George W. Bush (Pete Souza/The White House)

Carter and Clinton: Jimmy Carter (39) and Bill Clinton (42) aren’t the best of friends. Okay, they aren’t friends at all. Remember this Oval Office photo from President Obama’s first inaugural? If Carter stood any further away from Clinton he’d be in the Old Executive Office Building. But there’s 42 laughing with his arm around 39 and 39 doesn’t seem to mind at all.

Clinton and Obama: President Obama (44) and Clinton have long gotten over the bruising 2008 Democratic presidential primaries. Now that they are both two-term Democratic presidents, there are plenty of smiles to share. Besides, 42 is hoping his wife will run to be No. 45, a glass-ceiling-shattering achievement that an endorsement from 44 would help.

Clinton and Bush: Bush (43) ran for the presidency in part by promising to “restore honor and dignity to the White House.” That was a not-so-thinly veiled smack at Clinton’s affair with an intern that got him impeached. Meanwhile, 42 left the White House with a budget surplus, which 43 blew on a massive tax cut, two wars and a Medicare prescription drug plan.

Obama and Bush: Obama ran for president promising to jettison just about everything done by his predecessor. And once in office, 44 blamed 43 for the nation’s economic mess and sluggish recovery. Other than that, there’s not much of a beef between 43 and 44. The same cannot be said about Bush’s former lieutenants.

Knowing all this, the laughs, the physical contact and the genuine pleasure in each other’s company (at that moment, anyway) is truly a remarkable thing to behold. There was a time when that kind of camaraderie was not just the province of the presidents’ club. It’s what got things done at both ends of Pennsylvania Avenue. Those were the days.

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