The latest flare-up of violence in Baghdad resonates like an echo of the bad old days. A suicide bomber killed 29 worshippers at a Sunni mosque Sunday night, including a member of Parliament. Other attacks around the city, against Sunnis but also at least one bombing in a Shiite neighborhood, brought the day's death count to at least 35.

The attacks have already invited comparisons to the 2006 bombing in Samarra, because of their size and the sectarian provocation they represent.

Meanwhile, Moqtada al-Sadr, back from exile, is making attempts at resurgence as a domestic force and king-maker, or at least an undoer. The Washington Post reported Saturday on his new call to followers to protest against the government of Prime Minister Nouri al-Maliki. (By way of a metric of success, the protests were to continue for as long as U.S. troops remain in Iraq, Sadr said.)

Renewed sectarian violence and the return of Moqtada al-Sadr are interesting developments on their own merits. They're even more so when they coincide with widely expressed concerns that other revolutions in North Africa and the Middle East not lead to "another Baghdad," or another Iraq. Such arguments are often wise, and even grounds for optimism (as this one, Andrew Gilligan's take on Tripoli's chance for orderly transition, is). But for readers in the West, the past tense is implicit. The new revolutions need not be how Iraq was. 

The latest headlines serve as a reminder that that troubled country, much improved though it seems to be since the worst days of 2006, is still with us, and still bedeviled by the events that have defined the last decade for Iraq and the U.S. alike.