He couldn’t get Obama to bomb Syria—or make a cancer victim stop tweeting. So maybe Bill Keller felt it was time to move on.

Keller, increasingly an embarrassment at The New York Times as a columnist—after an up-and-down tenure as chief editor—announced tonight he is exiting the paper, just a month after he drew wide scorn for a column bullying a cancer victim, which was not mentioned in the Times’s release.

Bill Keller, a columnist at The New York Times and its former executive editor, will leave the paper to become editor in chief of The Marshall Project, a nonprofit journalism start-up focused on the American criminal justice system.

“It’s a chance to build something from scratch, which I’ve never done before,” Mr. Keller said, “and to use all the tools that digital technology offers journalists in terms of ways to investigate and to present on a subject that really matters personally.”

Keller had recently supported a US attack on Syria—apparently learning nothing from his boosterism of the US invasion of Iraq. He fully backed Judith Miller in the Scooter Libby case. He also famously mocked Julian Assange (after exploiting all those WikiLeaks leaks). Did not allow his paper to call torture torture. Held that James Risen scoop—for a year—that might have elected John Kerry in 2004. Mocked Baby Boomers with far less money than he has for expecting so much in “entitlements.” I could go on.

Top executives at the Times nevertheless expressed surprise and wished him well.

“Bill has made so many contributions to The Times over his 30 years here, it’s difficult to quantify them,” said Arthur O. Sulzberger Jr., publisher of The New York Times. “He challenged his newsroom colleagues to innovate while remaining true to the highest journalistic standards, and we’re all better for it.

One could have some fun with that, but I will try to resist.

Note: Keller figures prominently in my book on the US media and the Iraq war, So Wrong for So Long.