First Mexico, now Iraq:

A U.S. military brigade is constructing a 3-mile-long concrete wall to cut off one of the capital's most restive Sunni Arab districts from the Shiite Muslim neighborhoods that surround it, raising concern about the further Balkanization of Iraq's most populous and violent city.

U.S. commanders in northern Baghdad said the 12-foot-high barrier would make it more difficult for suicide bombers to strike and for death squads and militia fighters from sectarian factions to attack one another and then slip back to their home turf. Construction began April 10 and is expected to be completed by the end of the month.

Although Baghdad is replete with blast walls, checkpoints and other temporary barriers, including a massive wall around the Green Zone, the barrier being constructed in Adhamiya would be the first to be based in essence on sectarian considerations.

Hell, why stop there? I say we turn the entire city into a series of square-meter cubicles, each with their own personal security detail. And we can connect them with an intricate labyrinth of hamster tubes!