Now, as we explain in our Chronicle story Thursday, Newsom is leading the charge to legalize marijuana for adult recreational use in California.

His fellow advocates, many of whom have long toiled in anonymity, agree that having the Lite Guv of the world’s eighth-largest economy leading the charge on a social issue is a good thing.

“It’s amazing to have Newsom come out on this,” said Neill Franklin, retired Maryland State Police major who is now the executive director of LEAP (Law Enforcement Against Prohibition). “It shows his courage.”

Ah, yes, courage. Often a character trait in short supply among politicians.

Newsom admitted that he has long supported legalizing pot, but didn’t have the courage to “come out” about it until about a year ago. The turning point? When many of his fellow Democrats privately said they supported abolishing the death penalty but didn’t stand up for the2012 state ballot measure that would have done so. It failed.

“I was floored that all my friends — Democrats — were nowhere to be found on that statewide,” Newsom said. “And I thought, ‘You’ve got to be kidding.’ I’ve heard them all give speeches on it.”

“It was just frustrating and I said, ‘I’m not going to do this anymore,’ ” Newsom said.

So let’s talk raw politics. Newsom is a guy with political ambitions, right? (Starting with his re-election campaign next year.) Isn’t being pro-legalization at a time when few others are a political liability?

Let’s now go to the San Francisco Chronicle/SFGate.com’s Shaky Hand Productions for a clip of the LG answering that very question:

[youtube http://www.youtube.com/watch?v=Yb3TA88Nv1U]

Authenticity. That’s a word we first heard the LG use when we had breakfast with him in Austin, Texas, in 2008 after he gigged at the Netroots Nation liberal bloggers conference.

So speaking of authenticity, one question that’s bound to be out there: Will it hurt the legalization message to have Newsom fronting it, especially given his own battles with alcoholabuse when he was San Francisco mayor?

In 2007, Newsom sought treatment after having an affair with an employee in his office, Ruby Rippey-Tourk, who happened to be the wife of a top political aide.

“I don’t connect that dot at all,” Newsom said Thursday. He referred to his substance abuse issues in the past as “drinking too much wine.”

And we also asked if he was an active — as in current — smoker of marijuana.

“Unequivocally, absolutely not,” Newsom said. “I get nervous about this as a parent. I don’t like it. I don’t like the smell. I don’t want to see it. It’s not my thing. I don’t think it’s particularly healthy for a lot of the folks who I know that use it. That’s not what this is about.”

For Newsom, legalizing marijuana is about the failed U.S. drug laws, and a drug war where millions are spent on arresting people for possession of marijuana — often in racially biased ways. That’s money that could be spent, he says, on curbing violent crime.