Goodbye, Obama: the outgoing president leaves a loaded gun in the Oval Office.

• Author: Healy, Gene

In the presidency's long march toward full-spectrum dominance over American life, the POTUS has become, among other things, host in chief of our national talk show. Barack Obama fulfilled that role better than most. Our 44th president never seemed more completely in his element than when trading zingers at the annual White House Correspondents Dinner. We find it reassuring somehow to be reminded that the guy with the kill list has a sense of humor.

AT THE 2015 version of the annual press and pols confab, Obama got one of his bigger laugh lines when he joked: "Dick Cheney says he thinks I'm the worst president of his lifetime. Which is interesting because I think Dick Cheney is the worst president of my lifetime." But the jibe had a funny-because-it's-true element that Obama didn't intend. As George W. Bush's "co-president," Cheney repeatedly described the team's mission as "leaving the presidency stronger than we found it." In that respect, Cheney and Obama have more in common than either would care to acknowledge.

As a young man, biographer David Maraniss reports, Obama developed "an intense sense of mission...sometimes bordering [on] messianic." By the time the Oval Office was in his sights, he'd decided "his mission was to leave a legacy as a president of consequence."

Mission accomplished: As Obama's tenure comes to a close, it's clear his has been a presidency of enormous consequence. But his most lasting legacy will be one few--perhaps least of all Obama himself--expected. He will leave to his successor a presidency even more powerful and dangerous than the one he inherited from Bush. The new powers he's forged now pass on to celebreality billionaire Donald J. Trump, a man Obama considers "unfit to serve as president"--someone who can't be trusted with his own Twitter account, let alone the nuclear launch codes. Perhaps only those incorrigible "cynics" Obama regularly chides from the bully pulpit could have predicted this would come to pass.

'I'LL TURN THE PAGE ON THE IMPERIAL PRESIDENCY'

IN HIS LONG-SHOT bid for the 2008 Democratic nomination, then-Sen. Obama ran as as a forceful critic of executive unilateralism-one, unlike the other leading contenders, untainted by past support for the Iraq war. A speech he'd given at an anti-war rally in Chicago in 2002 as an obscure state senator running for the U.S. Senate would become a key element of his sales pitch on the path to the presidency.

That speech, railing against a "dumb," "rash" war, had barely registered at the time; in 2007, the Obama campaign couldn't even find usable video of his remarks. "I'd kill for that," chief strategist David Axelrod lamented. "No one realized at the time it would be a historic thing." Still, the Obama team unearthed enough audio to hawk a cellphone ringtone "with 'what I do oppose is a dumb war' over a hip-hop beat."

On October 2, 2007, trailing far behind then-Sen. Hillary Clinton in the polls, Obama delivered a major campaign address at DePaul University in Chicago, timed to mark the fifth anniversary of the "dumb wars" speech. "Five years ago today, I was asked to speak at a rally against going to war in Iraq," Obama told the students. Yet Congress voted "to give the president a blank check" that left America "mired in an endless war."

"We all know what Iraq has cost us abroad," Obama declaimed at DePaul, "but these last few years we've seen an unacceptable abuse of power at home.... We've paid a heavy price for having a president whose priority is expanding his own power." If elected, he pledged, he'd "turn the page on a growing empire of classified information" and "turn the page on the imperial presidency." "It's easy to be cynical" about politicians' promises, Obama closed, but "I'm running for the presidency of the United States of America so that together we can do the hard work to seek a new dawn of peace."

As a presidential candidate, Obama made clear that, along with "dumb wars," he firmly opposed unauthorized wars. That December, in a candidate survey on executive power conducted by reporter Charlie Savage, Sen. Obama stated plainly: "The President does not have power under the Constitution to unilaterally authorize a military attack in a situation that does not involve stopping an actual or imminent threat to the nation."

As Obama gained on Clinton in the following months, she was reduced to carping: "I have a lifetime of experience that I will bring to the White House.... Sen. Obama has a speech he gave in 2002." And yet that speech turned out to be instrumental to Obama's winning the nomination, and thus the presidency.

Obama's unlikely ascendancy culminated at Chicago's Grant Park on election night 2008. The National's "Half Awake in a Fake Empire," the campaign's semi-official hipster anthem, thrummed out over an ecstatic crowd of 125,000 as the president-elect prepared to take the stage. "If there is anyone out there who still doubts that America is a place where all things are possible, who still wonders if the dream of our founders is alive in our time-tonight is your answer," Obama proclaimed. "Change has come to America."

THE 'FOREVER WAR' PRESIDENT

"SHUT THE FUCK up!" Obama reportedly exclaimed on the early morning of October 9, 2009, when press secretary Robert Gibbs woke him with the news he'd won the Nobel Peace Prize. In...