Terrorist violence can make the previously unthinkable suddenly seem acceptable. The levels of surveillance introduced after 9/11 could have been considered reasonable only in the climate of collective panic that the attacks induced. But this week’s reaction to the fatal shooting of four Marines and a Navy petty officer in Chattanooga, Tennessee, by a 24-year-old Muslim has to win the prize for the worst proposed civil liberties infringement to come out of a violent disruption. No matter how high tensions may have run after the Boston Marathon bombing or 9/11, few dared to propose what figures of both left and right have now suggested: the segregation and internment of Muslim citizens.

The first mention of internment came from a somewhat unexpected source: Gen. Wesley Clark, a Democrat known for his progressive-oriented presidential campaign in 2004. Interviewed on MSNBC in the shooting’s aftermath, Clark said the U.S. needed to increasingly get tough on “radicalized” individuals. He spoke favorably of the internment camps set up during World War II, saying that “if someone supported Nazi Germany at the expense of the United States, we didn’t say that was freedom of speech. We put him in a camp.” Lest there be any doubt what Clark was advocating, he insisted that for radicalized Muslims, “it’s our right and obligation to segregate them from the normal community for the duration of the conflict.”

One might point out, in the first place, that the idea of detaining people for “the duration of the conflict” means, in practice, imprisoning them forever. Since the “war on terrorism” is a fight without end, it will never have some ticker-tape-strewn V-Day, and Clark’s suggestion is for the government to deem particular Muslims too radical to live freely and isolate them permanently in camps.