For two governments in a row, the posts of president, premier and parliament speaker have been parcelled out to a Kurd, a Shiite and a Sunni, all with deputies of the other two groups, a path analysts warn is dangerous.
"What we fear is a Lebanonisation and unfortunately, this is what is happening," said Mowafaq al-Rubaie, a former national security adviser, referring to Lebanon's codified distribution of power.
"Certain political parties, who claim to speak on behalf of a sect, believe that a Lebanonisation of the regime is in their interests."
For nearly 80 years, Iraq was ruled by its Sunni minority which did not cede power to the country's Shiite majority until after the 2003 US-led invasion. What followed were years of horrific sectarian violence which peaked in 2006 and 2007, when tens of thousands of people were killed.
A year ago, Iraq's political leaders all but made the new system official after more than eight months without a government following elections in March 2010.
They agreed to a government of national unity with the same outlines of one that emerged following the country's previous parliamentary elections in December 2005.
Jalal Talabani, a Kurd, would retain the presidency with a Sunni and a Shiite as his deputies; Nuri al-Maliki, a Shiite, would remain prime minister with a Sunni, a Kurd and a Shiite as his deputies; and Osama al-Nujaifi, a Sunni, was named speaker, with Shiite and Kurdish deputies.
Such an agreement is similar in construction to Lebanon, where power is shared between 18 religious communities in a quota system that applies not only to ministerial posts, but also to top officials.
For Ihsan al-Shammari, a political science professor at Baghdad University, "there are great similarities between the nature of the regimes in Iraq and Lebanon - the divisions are the same, based along ethnic and sectarian lines.
"The only difference," Shammari said, "is that here it is not written in the constitution like in Lebanon." The Lebanese constitution dictates that parliament seats be split between Muslims and Christians.
And the Taif Agreement that ended the 1975-1990 civil war says that the president must be Maronite Christian, the speaker of parliament Shiite and the prime minister Sunni, codifying an unwritten rule that dated back decades.
"Unfortunately (in Iraq), these quotas do not simply concern the three main posts - they have spilled over into government departments, and have had a snowball effect to the point of affecting who is chosen to work in parliament and government ministries, as well as the security forces," Shammari said.
As a result, many Iraqis now complain of being kept out of employment in their chosen profession as a result of their ethnic or religious background, details that were taboo, at least officially, in Saddam's Sunni-dominated regime.
And, much like Lebanon, neighbouring countries play major roles behind the scenes.
The fragile accord that led to the formation of Maliki's unity government reflected the balance of power in the region, with the US and its ally Saudi Arabia on one side, and Iraq's neighbour Iran on the other, according to experts.
Also like Lebanon, little in the way of legislation is passed through parliament - key issues such as a law regulating the energy sector, or reform of the mostly state-controlled economy have languished, while permanent ministers of interior and defence have yet to be named.
"All the parties have allegiances with foreign countries, and they have more (allegiances) than with their homeland," said Shammari.
"These links are the principal reason for the (political) deadlock." Rubaie, the ex-national security adviser, adds: "We cannot talk amongst ourselves, because we have allowed our neighbours to interfere."