FILE - This Aug. 17, 1969 black-and-white file photo shows music fans seeking shelter is a grass hut at the Woodstock Music and Art Festival in Bethel, N.Y. where the sign above reads "Have a Marijuana." It took 50 years for American attitudes about marijuana to zigzag from the paranoia of "Reefer Madness" to the excesses of Woodstock back to the hard line of Just Say No. And now, in just a few short years, public opinion has shifted so dramatically toward pragmatic acceptance of marijuana that even those who champion legalization are surprised at how quickly attitudes are changing and states are moving to approve the drug for medical use and just for fun. (AP Photo, File)