A country is invaded by a large army of coalition forces. Government officials and their supporters are killed and/or imprisoned, and a provisional coalition government is installed. The new government is made up of local leaders who are coalition-friendly. (Of course, they serve only as long as they do things the coalition's way.)
Anyone suspected of terrorism or even dissent is held without rights in prison camps. There are no trials. They are interrogated mercilessly.
The army expected to be greeted as liberators... yet the citizens don't react with appropriate gratitude to being freed from a system which has kept them under its thumb for so long. The army struggles to maintain order, even if it means civilian casualties in the hundreds of thousands, and the transformaiton of a once-beautiful country into a bombed-out wasteland.
The fragile order that the coalition forces are trying to maintain is shattered daily by insurgents, using guerilla tactics and improvised explosive devices to kill as many troops as they can. The insurgents are fighting a kind of war the army has never faced before: a war without uniforms or rules.
The insurgency grows stronger and more terror cells crop up daily. Longstanding cultural divides fuel the hatred and violence. More and more troops are killed each day by the insurgency, whose unconcealed agenda is to sieze back control of the newly-liberated country. The cost to the invading nations, in blood and treasure, is crippling.
You might have thought I was talking about Iraq. But this was actually the plot of the movie Red Dawn. Except the insurgents there were called "Wolverines." And those roadside bombers were played by guys like Patrick Swayze and Charlie Sheen, so they were the good guys.
One man's ceiling is another man's floor.