By Stephen Kalin and Kareem Raheem
BAGHDAD (Reuters) - A day after the year's deadliest attack in the Iraqi capital, supporters of a Shi'ite cleric took to the streets of Baghdad on Thursday to denounce the government for failing to protect them, escalating political confrontation that could doom the ruling coalition.
Suicide attacks on Wednesday killed at least 80 people and wounded more than 110 others, including civilians and security forces. Two more blasts claimed by Islamic State on Thursday left two policemen dead west of Baghdad.
The highest death toll was in Sadr City, a bastion of powerful Shi'ite cleric Moqtada al-Sadr, who has led protests in Baghdad since February demanding Prime Minister Haider al-Abadi replace politically-affiliated ministers with independent technocrats.
Hundreds of demonstrators protested in the poor district on Thursday, carrying placards denouncing Abadi, his predecessor Nuri al-Maliki and other top political figures, arguing that the entrenched political class had left them undefended.
"There needs to be a serious stance against all failed, corrupt security commanders who didn't protect the lives of innocent civilians and their property," said Ali al-Mahamdawi, 28, a protester and religion student.
"They protect and fortify the Green Zone but not their own sons," he said, of the heavily-secured sector on the banks of the Tigris that Iraq's government inherited from occupying U.S. forces.
Security has improved somewhat in the capital in recent years, even as Islamic State fighters seized swathes of the country almost reaching Baghdad's ramparts.
But the prospect raised by this week's carnage that Baghdad could return to the days when suicide bombings killed scores of people every week adds to pressure on Abadi to resolve the political crisis, or risk losing control of parts of the capital even as the army fights Islamic State in the provinces.
PRESSURE ON ABADI
Sadr's followers argue that the corrupt political system has undermined the fight against the Sunni Muslim militants, and have called for armed neighbourhood groups to take over from police patrolling city areas.
A Sadrist lawmaker even suggested that corrupt factions in the government may have been somehow responsible for Wednesday's bombings to punish people for demonstrating.
"The bombing that targeted the poor people in Sadr City reflect their legitimate demands for the removal of the corrupt, the partisans and those who want to hold onto their positions," Hakim al-Zamili said in a statement on Wednesday.
The Interior Ministry accused Zamili of spreading lies and said Sadr followers were contributing to the insecurity through protests that divert police resources.
The Sadrists were "putting the people's security at risk and causing them to worry every day, forcing the security services to mobilize a large part of their resources," the ministry said in a statement.
The interior minister belongs to the Badr Organization, one of Iraq's most powerful Shi'ite militias, which has grown in influence by helping to lead the fight against Islamic State, but which Sadr criticises for taking orders from Iran and defending party political interests.
Prime Minister Abadi, who took power after Islamic State fighters swept through Sunni areas of the country in a lightning offensive in 2014, has vowed to reduce the influence of sectarian political parties including from his own Shi'ite majority. But he depends on a coalition of powerful Shi'ite parties to retain power.
Abadi has proposed a technocrat cabinet, but parliament has failed to approve it. Lawmakers scuffled inside the chamber a month ago and have not convened a session since Sadrist demonstrators stormed the parliament building two weeks later.
Sadr, scion of a family of influential Shi'ite clerics -- Baghdad's mostly poor Shi'ite Sadr City district is popularly named for his father and father-in-law, both grand ayatollahs killed under Saddam Hussein -- gained influence during after Saddam's fall as an outspoken opponent of U.S. occupation.
He has lately reemerged as a foe of mainstream political parties, which mainly have sectarian roots and have divided power among themselves since U.S. troops pulled out in 2011.
The return of large scale bloodshed to the capital helps his argument that the governing factions have lost their grip.
"Yesterday's security blunders put pressure not only on Abadi but the entire political process," said Baghdad-based analyst Ahmed al-Sharifi. "All the blocs are responsible and subject to blame for what is happening."
LARGER ROLE FOR MILITIAS
Mowaffaq al-Rubaie, a senior Shi'ite member of parliament and former national security adviser, said he expected Shi'ite militias would push for a larger role in securing Baghdad as a result of the bombing. That would undermine Abadi's longterm goal of restoring more power to the regular army and police.
Asked if he thought militias would perform better than Iraqi security forces, Rubaie said: "They probably will."
Hatem Albu Ghunaima, a leader in Sadr's armed group, said: "Areas must be protected by local groups and not just here (in Sadr city). It should be in all of Baghdad and other provinces where the security situation is bad."
The deployment of additional militia fighters in Baghdad, which happened briefly this month after Sadr's supporters stormed into the Green Zone, raises the prospect of clashes between the competing groups.
The conflict is crippling state institutions and threatens to undermine U.S.-backed efforts to defeat Islamic State as well as international efforts to keep the major OPEC producer from bankruptcy amid low oil prices.
Parliament speaker Saleem al-Jabouri called for political parties to unite in the face of Wednesday's attacks: "The security of Iraq is more important than political considerations and personal interests."
Since 2014, Iraqi forces backed by U.S.-led air strikes have driven Islamic State back in the western province of Anbar and are preparing for an offensive to retake the northern city of Mosul. A government spokesman said on Wednesday Islamic State had lost two-thirds of the territory it seized in 2014.
Yet the militants are still able to strike outside territory they control.
"Who is accountable for yesterday's events? Is it only Daesh?" said Rubaie, using an acronym for Islamic State. "We are fighting Daesh, we know they are the enemy. They're bound to do it. But what about us? What have we done?"
(Additional reporting by Maher Chmaytelli and Saif Hameed; editing by Peter Graff)