After decades of suppression and marginalisation, the Iraqi Shias have emerged as a force to be reckoned with in Iraqi politics again.
The tens of thousands of demonstrators who took to the streets of Basra on Thursday to protest against US plans for a future Iraqi Government have sent a clear message to Washington about the risks of ignoring them.
The expression "Iraqi Shias" is often taken to mean a homogeneous group with unified political goals and ambitions distinct from, and sometimes contrary to, those of the second largest sect in Iraq, the Sunnis.
Shia demonstrators this week sent a clear message to the US
But experts believe that this is a gross oversimplification, and many Iraqis usually feel misrepresented when they are referred to by their sectarian denomination.
That is especially true of secularised Shias, who would rather be described as liberals or communists.
Urban Shias are also distinct from the tribal communities.
Even within the religious class itself, there are fundamental disagreements on the crucial question of the relationship between the state and religion.
Since the Iranian revolution, the image of a Shia cleric, with a black turban and a long white beard, has become synonymous with a radical Ayatollah bent on creating a theocratic state.
But the most senior Shia cleric in Iraq, Ayatollah Ali Al-Sistani, is actually among those who believe in separating religion from the state.
After the invasion of Iraq in March last year, he appeared to adhere to his quietist stance.
Ayatollah Ali Al-Sistani's image can be seen throughout Basra
He rarely made political statements.
That is why his recent public intervention in politics is a clear indication of a growing impatience among many of his followers.
It seems that he could no longer remain quiet when more and more of them feared that American plans for the transfer of power would undermine their aspiration for a representative democracy.
That could eventually favour their interests as the majority in Iraq.