You are simply wrong. The Mahdi army fought against us briefly in 2004, and then stopped directly opposing our occupation. Instead they have been working within the official government and at the same time have been heavily involved in the sectarian violence. They have not been attacking our forces for quite a while, and they certainly would not be attacking themselves while they were wearing those Iraqi Army uniforms rather than their militia uniforms. Basra has been mostly peaceful since early after the war started. The only major violence appears to be initiated by the Brits who every now and then take it upon themselves to knock over a police station.
You really should research the subject. The term insurgency is interchangable with the phrase 'sunni insurgency'. That you are not aware of this is stunning.
"Whereas the Vietnam War was a Maoist people's war, Iraq is a communal civil war. This can be seen in the pattern of violence in Iraq, which is strongly correlated with communal affiliation. The four provinces that make up the country's Sunni heartland account for fully 85 percent of all insurgent attacks; Iraq's other 14 provinces, where almost 60 percent of the Iraqi population lives, account for only 15 percent of the violence.
The overwhelming majority of the insurgents in Iraq are indigenous Sunnis, and the small minority who are non-Iraqi members of al Qaeda or its affiliates are able to operate only because Iraqi Sunnis provide them with safe houses, intelligence, and supplies. Much of the violence is aimed at the Iraqi police and military, which recruit disproportionately from among Shiites and Kurds. And most suicide car bombings are directed at Shiite neighborhoods, especially in ethnically mixed areas such as Baghdad, Diyala, or northern Babil, where Sunni bombers have relatively easy access to non-Sunni targets"
http://www.foreignaffairs.org/20060301faessay85201-p10/stephen-biddle/seeing-baghdad-thinking-saigon.html"After U.S. forces overthrew Saddam in 2003, Sunni officers were initially dismissed, but belatedly invited back into leadership positions. Some have not returned, and are believed to be leading the insurgency against the Shiite-led government. An estimated 200,000 disaffected Sunni youths are the recruiting pool for the insurgency, John Reid, Britain's defense minister, said last week during a visit to Washington."
http://www.iht.com/articles/2006/04/12/news/sunnis.php"That policy guaranteed the acceleration of already growing tendencies in Iraqi society toward sectarian and ethnic violence – and possibly toward civil war as well as forms of "ethnic cleansing." Many of the Shi'ite troops and officers in the military and police commando units of the new Iraqi military are, in fact, motivated by hatred not just of Sunni insurgents but of the Sunni population as a whole. One fine reporter in Iraq, Knight Ridder's Tom Lasseter has, in fact, explored this new Iraqi reality on the ground in ways no other American reporter has thought to do. Last October, he "embedded" himself for a week in a unit of Lt. Gen. Petraeus's new military, the all-Shi'ite 1st Brigade, the first Iraqi unit to be given its own area of operations and often considered the template for the future of the army. What he discovered was a purely sectarian outfit obsessed with revenge against Sunnis. His is a chilling account of the violent Shi'ite hatred of Sunnis that drives Iraqi military operations in Sunni neighborhoods and essentially guarantees that the insurgency will only grow fiercer in response.
Lasseter found that Shi'ite officers and troops want to inflict death on a far broader swath of Sunnis than simply those insurgents they can identify. Their motive is clearly to intimidate the Sunni population into silence and acquiescence, while at the same time satisfying their own lust for revenge for past acts of oppression by the formerly powerful Sunni minority. One sergeant told Lasseter that, in 2006, the Shi'ites would "do what Saddam did – start with five people from each neighborhood and kill them in the streets and go from there." "
http://www.antiwar.com/engelhardt/?articleid=8453I could go on with link after link describing the ethnic makeup of the insurgent forces, however I rather suspect that you are not interested in the reality of the situation.