Martin van Creveld's The Blemish of Conquest
You won’t read the following block of text; it is too dense, too long and too serious. Nonetheless, I bring this excerpt from Martin van Creveld’s The Blemish of Conquest, because the entire thing is a great read, and I in particularly thought the the summary worth reprinting.
The third of Dayan’s observations, and the most relevant to a comparison with the current war in Iraq, is that the Americans found themselves in the unfortunate position of beating down the weak. As Dayan wrote, “Any comparison between the two armies was astonishing. On the one hand there was the American army, complete with helicopters, an air force, armor, electronic communications, artillery, and mind-boggling riches; to say nothing of ammunition, fuel, spare parts, and equipment of all kinds. On the other there were the [North Vietnamese troops], who had been walking on foot for four months, carrying some artillery rounds on their backs and using a tin spoon to eat a little ground rice from a tin plate.“
That, of course, was precisely the problem. In private life, an adult who keeps beating down a five-year-old—even one who had originally attacked him with a knife—will be accused of committing a crime; he will lose the support of bystanders and end up being arrested, tried, and convicted. On the world stage, an armed force that keeps beating down a weaker opponent will be seen as committing a series of crimes; therefore it will end up losing the support of its allies, its own people, and its own troops. Depending on the character of the forces (whether they are draftees or professionals), the effectiveness of the propaganda machine, the nature of the political process, and so on, this outcome may come about more or less quickly. But it is always the same. He who does not understand this does not understand anything about war—or, indeed, about human nature.
In other words, he who fights against the weak—note, in this connection, that the rag-tag Iraqi militias are very weak indeed—and loses, loses. He who fights against the weak and wins, also loses. To kill a much weaker opponent is unnecessary and therefore cruel; to let that opponent kill you is unnecessary and therefore foolish. As Vietnam and countless other cases prove, no armed force, however rich, however powerful, however advanced, or however well motivated, is immune to this dilemma. The end result is always disintegration and defeat; if American troops in Iraq have not yet started fragging their officers, the suicide rate among them is already exceptionally high. That is why the present adventure will almost certainly end as the previous one did; with the last American troops fleeing the country while hanging onto their helicopter skids.