I think war is used more in the sense of a "mission" in such cases. People see the single-mindedness, cooperation and the spirit of sacrifice that happen during a war, and wonder if why we cant bring that to bear against the other challenges we face.

At work, we sometimes set up a "war-room" during production downtime - again the logic is the same : we need to work with single-minded focus on this one problem and all else is secondary to getting the system up again.