Its difficult putting together an Iraqi military unit that can fight up to American (or Western) standards. Even under Saddam, the most reliable and effective units were kept together by clan and tribal affiliations. Even then, hard training was difficult. Iraqi officers tended to control their men via terror, or bribes, rather than leading them. To train effectively, you have to lead. So the American trainers of the 36th battalion had to teach the officers and NCOs new methods of managing their troops. This was not impossible, just time consuming. Iraqis have been moving to the United States for decades, and adapting to the different customs they encountered. Same thing with the hundreds of Iraqis who have been in the American armed forces. But in Iraq, the change was time consuming. There was trial and error in deciding who to accept, who to keep and what training and leadership methods would work best. Training the new Iraqi armed forces has been one big experiment. Knowing that, since the nations creation, the military had been more a source of tyranny, rather than protection from enemys, there has been a search for ways to build a different kind of army. The idea was to create an armed forces that was both effective, and willing to always obey the elected leadership of the country. Iraqis have been trained to fight effectively, but whether they will be loyal to their government is not yet known.
The 36th battalion is also known as the commando battalion because many of its 400 or so troops have been trained to the point that they can carry out commando type operations.
In order to jump start the creation of a new Iraqi army, American trainers (mainly Special Forces) have been actively recruiting Iraqis willing to train hard, follow orders from the Iraqi government and take on difficult missions. This includes jobs like clearing gunmen out of mosques and taking on heavily armed warlord militias. The new units have been in training for nearly a year. The units mix Shias, Sunnis and Kurds together. They are all volunteers and the American recruiters make sure they understand what they are getting into. That includes working well with people you would normally not work with. There are a disproportionate number of Kurds in the units, which has caused some concern within the Iraqi government. The Kurds have been basically independent from any Iraqi government since the early 1990s, and both Shia and Sunni Arabs are unsure if they will be able to make the Kurdish territories a real part of Iraq again. But once the Kurds train with the Arabs, and those who cant handle the training are removed, the units come together. Only one of these battalions, the 36th battalion of the Civil Defence Corps, has been in action. But others are being recruited and trained.