It's understandable if you mistook Jack Black for a slacker considering that his career began with roles in stoner comedies. In 1998, Black - who turns 47 today - played the drug guru Devlin in Bongwater, starring Luke Wilson and Brittany Murphy. And in 2002, he had a breakout role in the comedy Orange County as the burnout Lance Brumder, who ironically helped out his younger brother one night by getting high and burning down the admissions building at Stanford University. 

But unlike his early film characters, Jack Black is super ambitious. In a 2003 interview with Dave Grohl of Nirvana and Foo Fighters, Black revealed what he would do if he became America's first monarch since George III.

"You know what I'd do if I were king?" Black said during the chat for Interview Magazine. "I would legalize all drugs. All of them."

"Jack! Why?" Grohl gasped. 

"This is my theory: everyone does drugs and gets addicted to them because they're so naughty. But if you take that away--"

"They're boring," Grohl chimed in.

"Yeah, and I don't think it would be as big a problem. Plus you wouldn't have people [selling drugs] on the street. They'd be in the drugstore."

Black may have had a point. In 2001, Portugal decriminalized all drugs. Instead of combating drug use with a tough-on-crime agenda, the Portuguese government treated addition as a public-health issue. The results so far have been positive: the country's overall drug usage is down, the number of overdoses has plummeted and the spread of infectious diseases like HIV and hepatitis among drug users has also declined.

But no country has dared go as far as Black would, so there is still work for him to do if he ever does become king.

Unfortunately, the cameras weren't rolling on the interview. But the two have collaborated on film a few times. If you didn't already know, Grohl plays the devil in the video for Tribute, the 2002 hit for Black's band Tenacious D. Scroll down to see a behind-the-scenes video of Grohl hanging out with Black on the set for "Tribute." 

And here's Black singing some Christian pot rock in a clip from "Bongwater."

Banner image: Jack Black at "The World's End" Premiere at the ArcLight Hollywood Theaters on August 21, 2013 in Los Angeles, CA (Helga Esteb / Shuttertstock.com)