In 2006, I worked for the subcommittee in the House of Representatives that was the principal oversight body of the federal drug war. We were the ones responsible for the Combat Meth Act (inserted in the renewal of the Patriot Act), which federalized the restrictions on pseudoephedrine sales.
The thinking was that there seemed to be a real chance of truly ending meth production and consumption - a rare, total victory in the war. The precursor chemicals needed to make meth were produced only in Germany, India and China, and if those exports could be reliably controlled, restrictions on pseudoephedrine sales here could mean the end of the meth problem entirely. Apparently, the precursor chemicals are still finding their way to Mexico and the U.S.
Undoubtedly, the new law led to a noticeable decline of local "mom-n-pop" meth labs - dangerous productions sites that produced five pounds of toxic waste for every pound of meth. As usual, emotion was a big part of the arguments for it, with stories and pictures of redneck mobile homes or motel rooms polluted with chemicals, and men in biohazard suits carrying out children and hosing them down.
But, as with everything done in the drug war, we were just squeezing the balloon. That same year, we were in Mexico City and met extensively with government officials regarding the meth problem. At that time, they firmly denied that any meth was being produced there, much less exported to the U.S. Today, of course, all must admit that meth has now become a significant product of the Mexican cartels, and thus a driver of the horrible violence south of the border. Not only that, the "crystal meth" they send north is much more potent than what was normally produced locally.
In the end, we squeezed domestic production, and thereby created a tremendous opportunity for the cartels that they are ruthlessly exploiting.
Opposition to the drug war does not indicate a cavalier attitude to the destructive power of addictive substances (like, you know, alcohol). It is simply an honest recognition that there are limits to what big government can achieve, as well a recognition that the costs of prohibition far outweigh its alleged benefits.
People want drugs. Our moral outrage at the wreckage they cause is not a sufficient reason to criminalize their use. Alcohol prohibition taught us that. We should legalize (or at least, decriminalize, as Portugal has done with great success) and regulate production, and pour into rehab all the money we save by no longer caging casual users.