To detractors, Iraqi Prime Minister Nuri al-Maliki threw down the gauntlet with stunning speed when his Shi'ite Muslim-led government demanded the arrest of a Sunni Muslim vice president seemingly moments after the departure of U.S. troops.

Already seen as having autocratic tendencies in a country where most people have known little but dictatorship, Maliki has long expressed doubt about the efficacy of his brawling partnership government of Shi'ite, Sunni and Kurdish factions.

But the move to arrest Vice President Tareq al-Hashemi and a demand that parliament remove Maliki's Sunni deputy, Saleh al-Mutlaq, ignited a political storm that threatens Iraq's shaky U.S.-backed coalition and, for some, has called into question Maliki's commitment to any sort of democracy.

There is no doubt (the arrest warrant) was choreographed to put down the marker, to eradicate any doubt over who was in charge in the wake of the U.S. troop withdrawal, said Ali al-Saffar, an analyst with the Economist Intelligence Unit.

The political turmoil and its sectarian undertone so soon after the exit of the last U.S. troops in mid-December is bound to unsettle Iraq's Sunni neighbours, many of whom already disliked Maliki for his close ties to Shi'ite Iran.

STRONGMAN?

Less than nine years past the end of Saddam Hussein's brutal reign, the word dictator springs easily to the lips of Iraqis, many of whom question Western-style democracy and readily admit that they believe their country needs a strongman leader.

Maliki emerged in 2006 as a shrewd political operator able to meld rival factions and built his reputation as the Shi'ite leader who pulled Iraq back from the brink of civil war. Initially seen as a Shi'ite Islamist, he won respect from Sunnis

by sending the army to crush Shi'ite militias in the south.

Although hardly a clear choice -- his Shi'ite-led coalition failed to win the most seats in the 2010 election, Maliki muscled his way to a second term as prime minister in a power-sharing deal when no better option emerged.

While Maliki has suggested that power-sharing won't work, he has spoken just as frequently about following the constitution.

We have many problems that we cannot resolve through consensus due to differences in understanding and planning, Maliki said last month. But the supreme, holy, respected document is our constitution, on which we took an oath.

ISLAMIST ROOTS

Maliki was a student when he became involved with the Dawa party, founded in the late 1950s to promote the role of Islam in public life in response to rising secular Arab nationalism.

Dawa was driven underground after Saddam took power in 1979. Maliki was condemned to death as he agitated against Saddam from exile, mainly in Iran and Syria.

Highly strung and scowling, usually with a five o'clock shadow, Maliki may be the flip-side of the smooth, ingratiating politico in the Western mould. He speaks sharply, appears quick to anger and reputedly has a long memory for grievances.

While the view of many is that he is trying to consolidate power, Maliki has repeatedly argued that the charges that Hashemi ran death squads were brought not by him but by the legal system, and must be left to the legal system to resolve.

His advocates say this shows he is adhering to democratic norms, not abusing them.

Even if Maliki wants to be a dictator, said Sami al-Askari, a senior Shi'ite lawmaker, he cannot because the constitution, which distributes authority, and even the cabinet decisions, are done by voting, and he has just one vote.

REMINDERS OF SADDAM?

At a recent ceremony to mark the withdrawal of U.S. troops, people shouted, Long live Iraq, long live Maliki, the only leader of Iraq. A day later at another ceremony, the hall echoed with a song that praised Maliki as the shining sun who will banish the darkness of the night.

To some, such public homage evokes memories of Saddam.

More tangible and more worrying to others are the security ministries, which remain under Maliki's firm grip more than a year after he named his cabinet. He appears unlikely to let go of them any time soon.

The authoritarian aspects of his (Maliki's) rule involve centralising control of the security forces, seeking to influence the judiciary and trying to build tribal power bases in Sunni areas, said Reidar Visser, editor of Iraq-focussed website www.historiae.org.

In a recent editorial, Iyad Allawi, one of the premier's main political rivals, said the intelligence and security agencies had become a virtual extension of the Dawa party.

The American withdrawal may leave us with the Iraq of our nightmares: a country in which a partisan military protects a sectarian, self-serving regime rather than the people or the constitution..., the editorial said.

WARY NEIGHBOURS

Like many of Iraq's Shi'ite leaders, Maliki is closely tied to neighbouring Iran and therefore at odds with regional power Saudi Arabia and its Sunni allies who worry about rising Shi'ite strength in the Middle East.

In many ways, Maliki's approach to regional relations is similar to the attitude he takes to domestic ones; they are deeply rooted in distrust and the feeling that neighbouring countries are involved in a nefarious conspiracy to keep his government from achieving success in Iraq, Saffar said.

That kind of paranoia may push him to overstep his bounds in domestic politics, some analysts say.

Whether Maliki triggered the political crisis intentionally or simply miscalculated, Kurdish analyst Hiwa Othman said his first concern as U.S. troops left Iraq in mid-December should have been security, not consolidation of power.

It was a clear signal on Maliki's side that 'you're either with me or against me. The Americans are out and there is a new sheriff in town' ... Part of it was due to his arrogance and on the other hand, his inability to calculate the consequences of his actions, Othman said.

But Maliki has shown himself adept at surviving these kind of crises before through shrewd politicking -- a cautionary note to anyone who believes he has gone too far this time.

I believe that he is trying very hard to bridge the gaps that currently exist with his partners, U.S. Ambassador to Iraq James Jeffrey said.

(Additional reporting by Suadad al-Salhy, Aseel Kami and Ahmed Rasheed in Baghdad and Jon Hemming in Arbil; Editing by Jim Loney and Mark Heinrich)