Why some gun controls increase gun violence

Moreover, even if we were to reenact the assault weapons ban, how could we deal with the millions of such guns already owned? Some people think a voluntary buy-back program would work. But it would be costly. And who might the sellers be? They would be individuals who valued the money more than the firearm. That would include low-income persons living in high-crime areas who obey the law but need a means to defend themselves. And who would keep the weapons? They would be individuals who valued the firearm more than the money. That would include criminals, terrorists and mentally deranged persons who are not motivated by financial incentives. 

That's Robert Levy, via Glenn Reynolds.

I'm afraid that often "what sounds good" to an unengaged electorate beats "what works" in our time here in America.