Baghdad ? Britain’s weekend handover of Basra province will have a limited effect on security in Iraq’s biggest oil region because rival Shiite warlords and local officials have been wielding the real power in the area.

The British have never sought to maintain the same level of control as the Americans did over the provinces the U.S. oversaw after the 2003 invasion. Since elections in 2005, southern Iraq has been under the domain of religious Shiite parties and their militia allies.

All of which means the British are handing over something local power players already possess.

“I don’t think there is a handover. You’ve never had real British control of Basra or the area,” said Anthony Cordesman, of the Center for Strategic and International Studies. “What you are really watching is a sort of nominal transfer of authority to the central government and Iraqi forces.”

Stability in Basra and southern Iraq is key not only to security, but also to whether the all-important oil industry will grow and attract vital international investment. The region contains most of Iraq’s proven oil reserves. If bloody fighting between Shiite factions returns, it will be hard to persuade companies to invest.

Security problems could also open the door to even greater influence by neighboring Iran and threaten land routes used by the U.S. to bring ammunition, food and other supplies from Kuwait to American forces to the north.

Last Wednesday’s triple car bombing, which killed at least 25 people in Amarah, shows how fragile security in the south is.

“I don’t know that there is going to be a security vacuum more than there has been,” said Frederick Kagan of the American Enterprise Institute. “The British haven’t been patrolling very aggressively anyway. The situation is never going to go back to the status before because all kinds of things have changed.”

Even though Britain had long seen its influence over events in southern Iraq diminishing, the mere presence of substantial British forces offered assurances the situation in the strategic area would not spiral out of control.

British officials have said they will retain the ability to help Iraqi troops quickly if widespread violence erupts, but they are also reducing the number of troops in the country from 4,500 to 2,000 by spring. In the months soon after Saddam Hussein was toppled, there were about 40,000 British troops in Iraq.

The main players in Basra and southern Iraq are the powerful Shiite entities – the radical cleric Muqtada al-Sadr and his Mahdi Army militia; Abdul-Aziz al-Hakim, leader the largest Shiite political party and the Badr Brigade militia, which has largely been absorbed into the Iraqi security forces; and the Fadhila party, which also has its own fighters and a member as Basra’s governor.

Michael O’Hanlon, a senior analyst at the Brookings Institution, said Shiite rivalries notwithstanding, the security situation is not so dire as it sometimes appears.

“The vacuum is already there. But I don’t think things are catastrophic. It is not anarchic and it is not a state of civil war,” he said. “It is more like the Wild West, or a region of competing mafia dons. That’s not good, of course, but it’s also not horrible.”

That focuses attention on Iraq’s mostly Shiite security forces, which are also infiltrated by the militias.

Basra police chief Maj. Gen. Jalil Khalaf – who survived two assassination attempts in a single week last month – doubts his own forces have the means to cope.

“Frankly speaking, we have rifles, machine-guns and a few armored vehicles, which aren’t as advanced as the British weaponry and are insufficient to maintain full control of the province,” Khalaf said this month.