WHEN British forces quit Basra city last December after spending almost five years there trying to establish law and order, it was said that they had outstayed their welcome and the task they had embarked on was better left to Iraqi authorities. The British army is now confined to an airport outside Basra from where it is carrying out its only remaining task in Iraq, that of training the Iraqi army and security forces. Reports from Basra in the past four months have spoken of a city at the mercy of rival militias involved in violent turf wars often related to control of Iraq's oil industry whose centre is in the area. Yesterday morning Iraqi army troops, numbered in some accounts at as many as 15'000, entered the city with the declared intent of pacifying the largest of the militias, the Mahdi Army which owes allegiance to Moqtada al-Sadr, the volatile anti-US cleric who commands widespread loyalty in Iraq's Shia community. The recent relative drop in violence in Iraq has probably as much to do with the cease-fire called by al-Sadr last August as to the American “surge”. The significance of the action at Basra was underlined by the presence of the prime minister, Nuri al-Maliki. who flew there to oversee it. Of equal significance was the statement by al-Sadr that he would order a nation-wide “civil revolt” if the Basra action continued. Some observers wondered whether he actually meant “civil war”.