New research finds that a national campaignâ’s anti-drug TV ads failed to convince young children and teenagers to stay away from marijuana and actually might have encouraged some to try smoking pot. In their 1999 to 2004 incarnation, the National Youth Anti-Drug Media Campaignâ’s TV ads â’either had no effects on kids or possibly had a boomerang effect,â’ said Robert Hornik, lead author of a new study and professor of communication at the University of Pennsylvania. The U.S. Congress created the anti-drug campaign in the late 1990s and gave almost $1 billion to it through 2004, according to the...