According to Edward Boyd (seen via Instapundit):
I know quite a few people in law enforcement. A few of them are narcotics detectives with local law enforcement agencies and one is with the DEA. About two weeks ago, one of the local detectives (with the Phoenix Police Department) told me that the street price of methamphetamine, cocaine, and non-hydroponic marijuana has risen since the Feds deployed national guard troops at the border. He also said that large quantities of methamphetamine and cocaine are a lot harder to find right now.
I'm reminded of the public service announcement on Saturday Night Live
during the 1970s from the Dope Pickers Union:
Every time you buy Mexican or Columbian pot, you put an American out of work!
I can't find anything about it online, probably because the people who found it funniest can't remember it.