As Mexican troops drove by in Humvees in downtown Juarez, Mexico, a textile salesman told a reporter, "The drug hitmen are in control here. Things are out of control, there's so much death. At six o'clock I go home and I don't go out at all after that. There are so many killings."
What will the U.S. military do? The last time that the U.S. Army invaded Mexico, according to a study by Army historian Matt Matthews, was June 12, 1919, when "soldiers under the command of US Brigadier General James Erwin attacked [Pancho] Villa's base and drove him out of Juarez."
Thomas E. Ricks covered the U.S. military for the Washington Post from 2000 through 2008.