Were Bush's Policies So Effective That They Reduced Drug Use Retroactively?

Last night a commenter asked about President Bush's assertion in his State of the Union address that "drug use among youth is down 19 percent since 2001." Judging from the Monitoring the Future Study, that seems about right to me. Between 2001 and 2005, for example, self-reported past-month use of illegal drugs fell from 11.9 percent to 8.5 percent among eighth-graders (a 29 percent drop), from 22.7 percent to 17.3 percent among 10th-graders (a 24 percent drop), and from 25.7 percent to 23.1 percent among 12th-graders (a 10 percent drop). A rough average of those declines is 21 percent.

A more important question is whether Bush's policies had anything to do with these declines. The peak year for past-month drug use among eighth-graders and 10th-graders was 1996, five years before Bush took office; past-month use among seniors peaked in 1997. Allowing time for any changes he implemented after taking office in 2001 to have an impact, I suppose Bush could try to take credit for the continuation of the downward trend after, say, 2002. But it's not clear how he thinks he accomplished that. By shifting the emphasis of the government's anti-drug propaganda from the hazards of illegal intoxicants to drug users' complicity in terrorism? By continuing the Clinton administration's cruel, dogmatic crusade against medical marijuana users? By putting Tommy Chong in jail for selling bongs?