Where the guns come from

Re “He let Mexico down,” editorial, April 18

Reinstating the ban on assault weapons in the U.S. may very well help ease drug violence in Mexico. No one can deny that thousands of guns purchased in the U.S. end up in the hands of Mexican cartels each year.

But the oft-cited statistic espoused by Mexican President Felipe Calderon and other politicians -- that 90% of the guns recovered by Mexican authorities originate in the U.S. -- is not accurate. The Bureau of Alcohol, Tobacco, Firearms and Explosives has found that about 90% of the guns traced by Mexican police can be traced back to U.S. gun dealers. But many of the weapons seized in Mexico cannot be traced at all, because they lack serial numbers or other identifying features.

These untraceable guns, which account for many of those seized by Mexican police, could come from anywhere in the world. With so much uncertainty, it is impossible to know anything for sure -- except that the U.S. accounts for a smaller portion of the guns used in Mexican drug violence.

Gray Beltran

Mission Viejo