ANALYSIS - Afghan assault puts U.S. troop surge to test

KABUL (Reuters) - A U.S.-led NATO force began a long-planned assault on the Taliban stronghold of Marjah in Afghanistan's southern Helmand province on Saturday.

At stake is proving that U.S. President Barack Obama's surge of 30,000 troops can achieve its goal of rooting out the Taliban and handing over pacified areas over to Afghan forces in anticipation of a U.S. troop drawdown in 2011.

* The calculation of U.S. commanders is that the long-planned and well-publicised offensive could help the U.S. military avoid the mistakes it made in Fallujah, Iraq, in 2004. That assault on a militant stronghold in Iraq destroyed much of the city and created considerable anger with the U.S.-backed government, anger that has yet to disappear.

* The advance warning may have given the militants plenty of time to dig in and lay booby traps that could prolong the fight. Residents say they are afraid to go outside for fear of all the booby traps and improvised explosive devices.

* A number of civilians have stayed behind and have been advised to stay inside during the attack. NATO has put much effort into ensuring that its operations avoid any harm to civilians. But the longer the battle lasts, the greater the risk of civilian casualties.

* Expelling the Taliban from Marjah and the area round it will deprive the militants of a major sanctuary in a centre of poppy production, and go a long way toward taming what is now Afghanistan's most violent province. But it will not wipe out the Taliban and some fighters are believed to have dispersed already, before the attack began.

* If NATO succeeds in putting Afghan forces in charge of the area, it will be up to the U.S.-backed government to begin providing services, jobs and protection to the people. Since the government officially cannot permit the production of poppy, used to make opium, it could have a problem keeping residents who rely on the crop for a living happy.

(For more Reuters coverage of Afghanistan and Pakistan, see: here) (Editing by Michael Georgy)