From a USA TODAY story on the newspaper shutdown:

Coalition officials worry about the spread of misinformation or outright propaganda because it can lead to violence and undermine efforts to stabilize Iraq. This week, a Baghdad newspaper run by followers of Shiite cleric Muqtada al-Sadr was shut down after coalition officials said the publication incited violence against the U.S.-led force occupying Iraq. Military officials say the newspaper, Al-Hawza, called on readers to take up arms against U.S. forces.
“It’s one thing to call us pigs,” one coalition official says. “But when you call on people to take up a rifle or take up a knife to slit the throat of the American pigs, that crosses the line. If we let this go on unchecked, people will die.”

A serviceman emailed me this morning: “As one of those ‘American pigs’ whose throat might be slashed by Al-Hawza incitement, I support the CPA’s decision.”