Daylong wave of violence in Iraq kills 89

The widespread and lethal nature of the attacks - compared with an average of 14 a day this year - frightened many Iraqis, because it suggested that radical Sunni insurgents, led by Al Qaeda in Mesopotamia, had regained the capacity for the kind of violence that plagued Iraq when sectarian conflict was raging in 2006 and 2007.

But it also demonstrated the multiple and simultaneous threats gripping the nation at this pivotal time, with Shi’ite militants being linked to the killing of American troops, and threatening more violence if the troops remain, and Iraqi forces clearly unable to preserve the peace.

“Our forces are supposed to have the intelligence capabilities to prevent these types of breaches,’’ said Shawn Mohammed Taha, a Kurdish member of Parliament who serves on its security committee. “The fact is, the insurgents have acted like our security forces don’t even exist.’’

No group claimed responsibility for the attacks. But in a voice recording posted on a website for Al Qaeda in Mesopotamia last week, a spokesman for the terrorist group said that it was preparing a wide-scale strike.

“I promise you that we are on the right path,’’ said the spokesman, Abi Muhhamed al-Adnani. “Thank God that we are doing very well here.’’

“Do not worry, the days of Zarqawi are going to return soon,’’ he said, referring to Abu Musab al-Zarqawi, the former leader of Al Qaeda in Mesopotamia who was killed by American forces in 2006.

The attacks came just two weeks after the Iraqi government agreed to formally negotiate with the United States about possibly leaving some troops in Iraq after the end of the year. It was Iraq’s deadliest day since July 5, when nearly three dozen people were killed in Taji.

“The insurgents are able to attack anywhere and everywhere, and no one can really stop them,’’ Taha said, adding that the United States has achieved little in trying to improve Iraq’s own intelligence operation.