Mosul could have become a very bad place to be. The northern city, Iraq's third largest, was a Sunni Muslim stronghold.
Mosul was where Saddam Hussein's sons Uday and Qusay were found and killed.
Mosul city centre buzzes with trade and chatter
It was where many of the senior officer in the Iraqi army were drawn from.
And through the city runs an ethnic fault line - there are long simmering tensions between the Kurdish and Arabic population.
Go to Mosul now and you find as close to normality as you can get in Iraq today.
There are certainly troops on the streets - both in vehicles and on foot, and there are helicopters thundering through the air - not for nothing is the 101st Airborne Division nicknamed the "Screaming Eagles".
But Mosul is radically different from Baghdad.
It is another, much more pleasant world.
There are small things, like the presence of an outdoor shooting range on the riverbank.
A steady flow of customers lift an air rifle to take pot shots at hanging plastic bags filled with red water.
A 'fun' shooting range is unthinkable in today's Baghdad
Only someone with a chronic disregard for their own health would raise anything resembling a gun in a public place in Baghdad.
The street markets are full; the produce is clean and fresh-looking.
And there is clearly money in the city; the gold market, a covered area in the heart of the city, is bustling.
Men sit behind the tills or re-arrange the window displays; women peek through shop windows, commenting to their friends.
There is hardly a word to be heard here against the Americans who run the city.
The comparative calm in Mosul has not come about by accident.
The Screaming Eagles may be a devastating fighting force. But their commander, Major General David Patraeus, confounds every cliché about an American military man.
He is a short, slight but wiry man with intense eyes that lock on to you when you talk to him. He is a charismatic leader.
And he is pursuing with considerable success a policy that seems to only be talked about in the capital, Baghdad.
"Grab them by the balls and their hearts and minds will follow," goes the saying in the US.
That is not General Patraeus' way.
There is a comparatively relaxed atmosphere in Mosul
On his way to inspect a water plant his troops have helped repair, a refurbished school and a new medical clinic, he explains what lies behind everything he and his troops do.
"Everything is about hearts and minds," he says, as the engines and rotors of his helicopter roar deafeningly overhead.
"Not just tonight's activities, but everything that we do is hearts and minds.
"Even when you're taking down bad guys you've got to do it in a way that does not create more bad guys than you're taking off the street.
"There's actually a sign in our command post," he adds, "that says 'We're in a race to win the hearts and minds of the Iraqi people. What have you done today?"
If you talk to the men and women who work directly with the General, some of them go starry eyed at the mention of his name.
But the message he preaches has gone all the way through the division.
Sipping a coffee after dinner in the canteen - or "dining facility" if you are an American GI - two sergeants mull over what the hearts and minds policy means on the ground.
Talk to the public affairs people at the division's base and they will tell you about the number of meetings held with local worthies; the number of schools done up and the way the rounding up of members of the old regime has been carried out with sensitivity towards the local population.
But to Sergeant Ted Vytlacyl, "hearts and minds" is a matter of basic philosophy.
"At the first level," he says, "it is recognising one another as humans in a co-operative venture. The second dimension of hearts and minds is the behaviour that comes out of this recognition."
His dinner companion Sergeant Ken Perkowski gives a concrete example.
"A really simple thing to do," he says, "is that you take off your helmet, you take off your sunglasses and you make good eye contact with the locals.
You are more likely to hear evening prayers than gunfights in Mosul
"And then you eat or drink with them. If they offer you a drink, sit down with them, have tea with them, have a coffee with them, have a soda with them."
It is hardly rocket science.
But it needs a huge cultural change to make an army behave like that.
It has happened in the north, and the result is an area that looks like it has got back on its feet, and could well stay there.