Pornography and Environmentalism
The New York Times had an article recently on attempts in California to require actors in pornographic films to use condoms. The actors had mixed feelings, stating that the requirement may reduce business and put people out of work.
I doubt they're arguing that condom use would reduce the amount of pornography that people bought, so what they're really saying is that the condom requirement would drive business towards out-of-California and out-of-the-US production (I know some of the half-dozens reading this blog live in Vancouver - maybe pornography will join the rest of the movie business in setting up shop in your city).
As an environmentalist, I've heard this argument before. The American timber industry uses it when arguing against forest protection, saying that will just increase the cut of rainforest timber, which the American companies are generously seeking to protect. Same thing has been said about other environmental standards, and about stopping investment in countries like Burma and apartheid-era South Africa. I hear it also for stopping land use protections: "if we shut down development in our county, it will just leapfrog to the next one over."
It's not a completely ridiculous argument, but it also puts us in a difficult situation. The effect is to say that we must do something wrong here, or others will do something wrong elsewhere. Something about that just doesn't feel right to me.