Indeed, the US admits that this is a possibility:
Maj Gen Graham Binns, the commanding officer of forces in south-east Iraq, said that the Iraqi army had been rated capable of imposing order on the city without back-up from UK forces stationed at Basra air station and in Kuwait.
But a severe bout of violence would trigger a call for the fire-power of allies in the US-led coalition.
"We are a coalition and if additional troops are required, they could come from within our reserve or from within the coalition," Gen Binns said.
"I wouldn't have recommended bringing down troop numbers to 2,500 if I thought that would happen but you have to lean into this to make progress."
His comments follow warnings from US officials that a British withdrawal would leave US forces having to intervene in the south, while heavily committed elsewhere in Iraq.
To me, it makes little sense to prepare to intervene if things get worse rather than send a brigade combat team before problems arise in order to forestall such problems and bolster Iraqi efforts to enforce control. If our Marines want another job after Anbar is judged secure, I think Basra and the south would be a good opportunity for the Marines.
I suspect that press reports of how bad it is in the south are no more accurate than their constant predictions of doom in the rest of Iraq or Afghanistan. But it is important to keep threats from emerging within the Shia community. Even narrowly supported confrontations orchestrated by Iran must be combatted carefully lest fellow Shias show sympathy.
Putting Marines there would probably scare Iran too, perhaps deterring some interference, given that Marines are likely still itching to get revenge for the Beirut Marines barracks bombing nearly a quarter century ago that Iran orchestrated.
We've beaten the Sunnis and gained the support of most Shias, but both communities can still be a source of problems if not addressed early.
