THE latest bad news from the world of methamphetamine is that makers of the drug have perfected a one-pot recipe that enables them to manufacture their highly addictive product while on the move, often in their car. The materials they need — a two-liter soda bottle, a few cold pills and some household chemicals — are easily obtained and easily discarded, often in a trash bag dumped along the highway. There is, however, a simple way to end this mobile industry — and, indeed, most methamphetamine production. We’ve tried it in Oregon, and have seen how well it works. Just...