"war waged" is correct and usable in written English.
You can use it when you need to refer to a conflict or battle that has begun. For example: "The two sides entered a devastating war waged for months."
Consider the war waged by the terrorists.
It is a war waged on diversity".
And think of a holy war waged in space!
The country remains very weak after decades of continual violence, emigration, upheaval, return, clandestine war waged by neighbors, and overt war waged by international powers.
The violent birth of this nation has ceded to war waged like a computer game.
But it's a war waged with riding mowers that max out at seven miles an hour".
They refused to sit quietly and have the war waged in their name.
"This is the legacy of the holy war waged by the former FIA president," they said.
Meanwhile, the administration has just derived considerable political advantage from a war waged on false premises.
It was a war waged by purely mercenary Chinese, against the Malayan population.
The first of these was guerrilla war waged by peasant armies in the countryside.
