When the U.S. fought WW II there was no "proportionality". The Germans, the Japanese, the Italians are now our friends and allies to one degree or another. When we fought the "cold" war against the hegemony of the major communist states there was a measure of proportionality; yet, Russia and China, though not our friends in the same way as Germany, etc., are nonetheless involved with us in a more or less civilized way. As regarding the Korea and Vietnam wars, I would say they were more battles in the cold war than wars in themselves; and yes, we used proportionality in those conflicts. As a result we are still dealing with a major failure vis a vis North Korea. Vietnam, unlike states whose ass we properly kicked, is still pretty much an economic basket case whereas if we had used our full force then they would be much better off today; though I still claim we won that battle, just not decisively.
I think the problem with the current emerging world wide conflagration is that these people are so much different from us. We might as well be fighting aliens from another world. This is different from our previous conflicts in that these people are pre-medieval in their world view. We fail to understand what motivates them. We seem unable to accept that they don't want something "from us". They just want our destruction. One of their leaders said as much many years ago in a moment of candor.
We don't understand them. We are doomed to failure because we do not "know" our enemy. Lacking this knowledge we have a difficult time anticipating his next act of aggression. In fact, I am not so sure we even know ourselves anymore. This is a failure of leadership as much as anything. But I will tell you one thing. I believe our enemy is human enough to have his will broken and to do this the blood, as foretold in the Bible, will have to run in the streets to the depth of a horse's bridle. This can happen. Let them send a WMD into Tel Aviv or deal a major blow to America's heartland again.
The Greek historian Herodotus, writing about the Persian wars of 490 and 479 B.C., quotes the Persian king Xerxes:
"I intend to throw a bridge over the Hellespont, and to march an army through Europe against Greece, that I may punish the Athenians for the injuries they have done to the Persians....I...will not rest till I have taken and burnt Athens....if we shall subdue them, and their neighbors....we shall make the Persian territory co-extensive with the air of heaven; nor will the sun look down upon any land that borders on ours; but I...will make them all one territory, marching through the whole of Europe...no city or nation of the world will remain, which will be able to come to a battle with us... Thus, both those who are guilty, and those who are not guilty, must equally submit to the yoke of servitude."
Some of the rhetoric of the enemy is a mere echo of these sentiments.
Three hundred Spartans, at a mountain pass at Thermopylae, fought to the last man against Xerxes' army. In the valley below, the Greek army used this precious time to prepare to do battle against the invaders. The Greeks prevailed.
In a sense, Israel now fills the place of the Spartans giving the U.S. time to get its act together for the next chapter in this sad tale of which the current events are but a foretaste. God bless them for their service to a seemingly indifferent or even hostile human race. I for one, wish they would take the gloves off. Hell, I wish we would take the gloves off.