The most dangerous statement by a military man in modern times was uttered by Gen. Douglas MacArthur when he lectured his political master President Harry Truman in 1951 that in war, “there is no substitute for victory.”MacArthur had been in command of American and allied forces fighting the Chinese and remnants of the North Korean Army in Korea in early 1951 and he believed the only way to win in Korea was for Truman to allow him to fight the war in whatever way he deemed best.The writer is a serving colonel in the US Army. He commanded a combat battalion in west Baghdad in 2006 and holds a PhD in history from Stanford University. His book, Wrong Turn: America’s Deadly Embrace with Counterinsurgency, is due out by The New Press in April 2013. The views expressed in this article are those of the author and do not reflect the official policy or position of the Department of the Army, Department of Defense or the US government.If that meant taking the war directly to the Chinese, with the possibility of bringing about World War III, so be it, thought MacArthur. After all, a World War II hero who led Allied forces in the unconditional surrender of Japan, MacArthur believed that once war starts, military victory is the only goal and can have no substitute.The problem, however, is that MacArthur was wrong: in some wars, there are substitutes for victory. Sometimes the way a military fights a war results in it reaching a point where it is no longer worth the amount of blood and treasure invested to fight it in that way.When a military force commits to fighting a war in a certain way, and becomes morally bound to it, breaking the military away from that approach becomes very difficult. This is because military organizations by nature are disciplined and duty-bound organizations, and when they are told to fight, they operate under a basic assumption: they’re fighting to win.Combine this commitment with specific operational methodologies and the blood spilled in carrying them out, and a state can become burdened with an overly dogmatic military unable to see alternative paths. No wonder, therefore, that even today it is not uncommon to hear senior American military leaders repeating MacArthur’s dangerous phrase.THIS IS the current state of affairs for the United States in Afghanistan: An American army that has become trapped by a straitjacketed military approach according to which the only way to achieve America’s core policy goal in Afghanistan is armed nation building.Yet the core policy objective from the start of the war, as expressed clearly and repeatedly by senior American political and military officials, was the destruction of al-Qaida. A quite limited policy goal for sure – and one that was largely achieved only a few years into the war.Instead of grasping this basic strategic reality – that the US had achieved its core policy objective – the American military and its political masters convinced themselves that the only way to keep al-Qaida at bay was to build a modern state in the Hindu Kush.But nation building in Afghanistan to prevent the return of a handful of al- Qaida fighters is a military mission without end.I mean really, how long does it take to build modern, functioning states from scratch? It took the United States nearly 100 years to work out the fundamental social and political issue that divided it, namely slavery. In Europe it took hundreds and hundreds of years for small feudal entities to combine under centralized governments to form modern states.So why do the US and its military think that it can achieve this in Afghanistan in only a few years? Because the American military, with buy-in from its political leaders, has come to accept a narrative that says nation building anywhere in the world can be done, if only the right general is put in charge and the tactics are tweaked.FRENCH PRESIDENT Georges Clemenceau realized the problem of letting a military organization determine what victory should be in war and how to achieve it when he said at the end of the World War I that war was “too serious a matter to be left up to the generals.”Today in Afghanistan the effect of the American military’s embrace of and belief in the efficacy of armed nation building, with its never ending stream of statements of progress, has obscured the vast amount of blood and treasure invested in a military methodology that has not produced results. Yet still we hear the calls to try harder, stay a bit longer, and keep the faith that it will all turn out right, because in war there is, as they say, no substitute for victory.If the British had adopted such myopic, MacArthur-esque thinking in 1842 as they suffered military defeat in Afghanistan at the hands of angry tribesmen who wanted to be left alone, they would have never left. But the British did leave, and they departed because their intelligent strategic calculation told them it was no longer worth it to stay.Unfortunately MacArthur’s most dangerous thinking from 1951 is alive and well today in the American defense establishment and in the wonky policy world that supports it.RECENTLY, ONE of MacArthur’s loudest apparent disciples, neoconservative writer Max Boot, noted that there is a benefit from the American people not caring about the war in Afghanistan. Since they don’t care about the war, argued Boot, the American military can be left alone to finally “get it right.” MacArthur would have appreciated the implication of Boot’s words: leave the military alone to fight the war as they see fit.But aside from the militaristic ramblings of American defense experts, in a democracy the definition of victory and the means to achieve it cannot be left up to the military. Clemenceau was right, war is too important to be left up to the generals. But if a democracy does leave war up to the generals and unaccountable civilian experts like Max Boot, wars will never end until “victory” is achieved, even if the cost of pursuing that victory is no longer worth the effort.