On April 9th 2003 US troops and residents in Baghdad toppled a 20ft iron statue of now executed leader Saddam Hussein, signalling the end of his regime. But restoring order and stability in post-Saddam Iraq has so far proven impossible for coalition forces.
In a statement issued yesterday ahead of today's mass demonstrations, Mr al-Sadr branded US troops as the "arch-enemy" of Iraq.
"In order to end the occupation, you will go out and demonstrate," he said.
The feeling is reciprocated by the Americans, who hold the cleric responsible for a wave of sectarian violence across the troubled country.
But now Mr al-Sadr's political movement holds a quarter of the seats in prime minister Nouri al-Maliki's ruling alliance. The cleric himself was not expected to attend today's protests, which saw hundreds of thousands of people chanting anti-US slogans and waving giant Iraqi flags.
Accompanying the protests is a 24-hour total ban on vehicles in the Iraqi capital in an effort to end car bomb attacks.
US president George Bush intends to send 29,500 more troops to Baghdad in an effort to accelerate recent security initiatives.
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