Low intensity conflict
"Low intensity conflict means that thousands of people die but slower than if you dropped a bomb on them in one fell swoop. It means that you infect the heart of the country, that you establish a malignant growth and watch the gangrene bloom. When the populace has been subdued - or beaten to death - the same thing - and your own friends, the military and the great corporations, sit comfortably in power, you go before the camera and say that democracy has prevailed." --Harold Pinter 
Also see conflicts short of war.