[Arnfinn Madsen]

If it had been that simple, Ray, all military bases in Syria would have been bombed by US warplanes and cruiser missiles during this weekend. As they weren't, i.e. US (and most others) sees a point in not reacting disproportionally. There is actually a consensus that the reaction should be proportionate, but since that word has no agreed definition the international discussion centers around what is proportionate.

I think the consensus that it should be proportionate stems from a similar logic that existed through much of the cold war, each side wants to win, but also each side wants to maintain the state of a "limited war" as the consequence of a full war would be too devastating for both sides. If you stop keeping things inside proportion and scale this scenario up to a full war this actually again (as during the cold war) includes Russian nukes fired at New York.