Nuclear weapons are a deterrent and nothing more. Once the birds are aloft and heading to enemy territory, the enemy releases their missiles. Nuclear war by design can never occur. Assured mutual destruction defeats any war waged between enemies.
Nuclear weapon useage is not a victory, it is a defeat. No different than war is a defeat of diplomacy. There are no winners in a nuclear exchange. The bombs on Japan to end the assault on the USA during WWII, were never returned in retaliation. The entire nuclear war paradigm is a defeat of the reason for the war in the first place. It ends any mearsured approach to peace before or after the exchange of nuclear weapons.