Marijuana use rises in the U.S.

While the use of methamphetamines is waning, according to a national survey of drug use released on Thursday, Marijuana use is on the rise.

It seems that the next generation of recreational drug users are choosing to mellow out with the old classic.

How will this affect the legalization of pot?

More than a dozen states have approved the of medical marijuana, which is not legal under federal law. About half of those states regulate medical marijuana dispensaries.

The ominous-sounding letters from U.S. attorneys in recent weeks have directly injected the federal government back into a debate that has for years been progressing at the state level. Warnings in Washington state led Gov. Chris Gregoire to veto a proposal that would have created licensed marijuana dispensaries.

The Department of Justice said two years ago that it would be an inefficient use of funds to target people who are in clear compliance with state law. But U.S. attorneys have said in their recent memos that they would consider civil or criminal penalties for those who run large-scale operations — even if they are acceptable under state law