Victory, how does it happen?

Victor Davis Hanson addresses the question and gives the answers.
The Tragic Truth of War

What we dare not say: Killing the enemy brings victory.

by Victor Davis Hanson - National Review Online

Victory has usually been defined throughout the ages as forcing the enemy to accept certain political objectives. “Forcing” usually meant killing, capturing, or wounding men at arms. In today’s polite and politically correct society we seem to have forgotten that nasty but eternal truth in the confusing struggle to defeat radical Islamic terrorism....

....When an enemy finally gives up, it is for a combination of reasons — material losses, economic hardship, loss of territory, erosion of civilian morale, fright, mental exhaustion, internal strife. But we forget that central to a concession of defeat is often the loss of the nation’s soldiers — or even the threat of such deaths.

Like all his writings, it is well worth reading it all.