In some places it is with high level military war. Other places, most in fact, it is terrorism. Finally we should recognize the quiet "war" support, of fundraising, incitement, recruitment, even in the US.
The positive element of this story, is to strengthen Rusia, as a partner, in fighting the worldwide islamist terror campaign. I only wish that Britain, Germany, Italy, Spain, Canada were more vocally on board. France is, thus far, hopeless.
I expect civilization will win, but not before many lives are lost. I find islam's practitioners to be much like Japanese in 1945; requiring the same degree of defeat.
The scale and duration of the epic war are yet unknown. The casualty statistics are yet unknown. But it is a war; a war of unconventional character. Guerrilla war is the closest term we know.
There are two ways to combat guerrilla's: Try to sort them out from the so-called innocent civilians, or to wipe out the entire population, sufficient to convince them to stop--aka Japan 1945. The latter is quicker, saves our fighters' lives, is more certain. When/will it come to that?
USA, Russia and India divid the middle east and Islamic far east into zones of occupation, USA invades from the west, Russia from tne north and India from the east. We take the zones by force of arms and kill anyone that doesn't like it.
The above would be precided by a declaration of war against all nations ruled by Islamic Law.