The response from political journalists to yesterday’s announcement by Jim Webb that he was “seriously looking” at a 2016 White House run fell into two categories. Among some, there was anticipation and maybe even gratitude, since a Webb presidential campaign would give reporters something to write about other than Hillary Clinton. (As The Atlantic’s Molly Ball recently asked of Clinton’s seemingly inevitable presidential run, “Has America ever been so thoroughly tired of a candidate before the campaign even began?”) But others greeted Webb’s announcement with ridicule, including the Washington Post’s Greg Sargent, who tweeted that the former Virginia Senator was “‘Seriously Looking’ at himself in mirror in discussing fantasy White House Run.” As for me, I have no doubt that Webb is sincere when he says he’s thinking about running for president—and I also have no doubt that absolutely nothing will come of it.

The most important thing to understand about Webb is that he’s driven by anger and resentment. That’s not necessarily a bad thing. After serving as a Marine rifle platoon leader in Vietnam, Webb attended Georgetown Law School, where he was repulsed by his anti-war classmates who had dodged the draft. In The Nightingale’s Song, the author Robert Timberg recounts Webb’s experience at Georgetown in 1975 during the fall of Saigon:

Grabbing his books, he drove to school to study for his last set of exams, just days off. He arrived to find students gathered in animated clumps outside the law library, redeemed, intact, to Webb's eye secretly exchanging high fives. He spotted his Quaker friend, the one who had spent two years in Vietnam working in an orphanage, one of the few members of the class he respected.

"Are you really happy about this?" asked Webb.

"Yes, I am," replied his classmate.

"You make me want to puke," said Webb.      

Webb’s law school ordeal turned him into an impassioned and effective advocate for Vietnam Veterans who, he complained, were “invisible.” In books and in speeches, he implored Americans to give the men and women who’d fought in Vietnam the same respect they afforded those who’d fought in World War I and World War II. At the same time, he raised his public profile, eventually coming to the attention of Ronald Reagan, who in 1987 appointed him Secretary of Navy.

In 2006, Webb decided to run for the U.S. Senate as a Democrat out of anger at the Bush administration's handling of the Iraq War. “I’m finally frustrated enough that I think I'm gonna run,” he wrote to his friend, fellow Vietnam vet and former Nebraska Senator Bob Kerrey. On the campaign trail, Webb wore the combat boots of his son Jimmy, who was then serving as a Marine in Iraq, and frequently blasted Bush. After his election, Webb attended a reception for new senators at the White House where he met the president. The Washington Post reported on the encounter: 

“How’s your boy?” Bush asked, referring to Webb’s son, a Marine serving in Iraq.

“I’d like to get them out of Iraq, Mr. President,” Webb responded, echoing a campaign theme.

“That’s not what I asked you,” Bush said. “How’s your boy?”

“That’s between me and my boy, Mr. President,” Webb said coldly, ending the conversation on the State Floor of the East Wing of the White House.

Naturally, the reason Webb is now pondering a presidential run is anger—this time over the Obama administration’s new military campaign in Iraq and Syria and the Democratic Party’s hawkish turn. “Our country has been adrift,” Webb said yesterday. “We continue to be trapped in the never-ending, never-changing entanglements of the Middle East.”

Webb’s anger has served him—and, oftentimes, his country—well over the years. The problem with all of this is that once the proximate cause of Webb’s anger is resolved and his frustration dissipates, so does Webb’s interest in politics. He lasted just one year as Reagan’s Navy Secretary before resigning over proposed budget cuts. And he served only one term in the Senate, ultimately deciding not to seek reelection despite the fact that his biggest legislative priority, an ambitious plan to reform the criminal justice system, remained unfinished. “He loathed the elemental chore of incumbency—the endless fundraising loop—and was temperamentally ill-suited to the pace and grind of Senate work,” Newsweek’s Peter Boyer wrote. In the end, Webb preferred writing books.

While it’s possible that the Obama administration’s military campaign in the Middle East will continue to escalate, it’s hard to envision it turning into a catastrophe on the scale of Vietnam or the second Iraq War—and it’s equally hard to imagine Hillary Clinton, hawkish as she may be, morphing into a figure as loathsome, in Webb’s mind, as a draft-dodging Georgetown law student or George W. Bush. Absent those motivating factors, I just don’t see Webb—the rare politician who doesn’t crave the spotlight—sustaining a presidential campaign. After all, he’d been in the Senate for only a couple months when he complained to GQ’s Ryan Lizza that “To me, government is a cage.” If Webb felt cooped up in the Senate, wait until he gets to spend a couple days on a campaign bus barreling across Iowa.