Ygelsias suggests that the US Army is historically hopeless at counter-insurgency because of the strong Southern influence in the officer corps. His reasoning runs as follows: the Confederates chose to fight an all-out war with the Union, and when it went to ratshit they decided against fighting on as guerrillas and gave up in a gentlemanly fashion. Later, officership became a major career path for the sons of the old Southern elite, and later still with the social levelling of the second world war, for some of the sons of the impoverished Southern working class (it came with a free education). Hence, this supposed disdain for guerrilla warfare was institutionalised.
A couple of points. Some commenteers at Yglesias's and also at Lawyers, Guns and Money argue that either there was no guerrilla strategy then, that the South did indeed go guerrilla, or that a guerrilla movement in the face of an unsympathetic population had no chance.
The first is twattishly clueless. What about the people who gave us the word "guerrilla"? The Spaniards fought a hell of a guerrilla war from 1808 to 1813 against Napoleon, one that included essentially everything that you'll find in Mao and Giap. They were rooted in the population, mobile, avoided decisive actions, sought to wear down the French by protracted war, and prioritised attacking the puppet government the French set up so as to prevent it from stabilising. They used naturally defensible rear areas, in the mountains and semi-deserts, and also artificial ones - like the Lines of Torres Vedras, and in a functional sense the vast economic rear area of the British Empire. They operated in symbiosis with Wellington's army rather like the Vietcong's local and regional units with the Main Force and later the NVA - the French could never disperse enough to dominate the guerrillas for fear of Wellington smashing their detachments in detail, nor could they concentrate against Wellington for fear of the guerrillas. Eventually, having gone from organising local bands around the rear base to protracted war, they massed for the final confrontation at Vitoria in 1813.
Vo Nguyen Giap was a history teacher before he was a general. At his colonial lycée he taught the campaigns of Napoleon. One suspects he concentrated privately on the Peninsular War. That brings me to another point. Perhaps the best counter-insurgency leader the US Army ever produced was John Paul Vann, who was about as Southern as you can possibly get (brought up in a whorehouse in Norfolk, Virginia). But there's always an outlier or two.
On the other points, I disagree that the Klan amounted to a guerrilla movement. Its effectiveness as a terrorist organisation was based on the fact that the restored white rulers of the South were sympathetic to its aims and hence tolerated it, indeed encouraged it. It's more accurate to say it was/is a party militia, not unlike the Tontons Macoute of modern Haiti. The Southern elite, rather than going guerrilla, went on the Long March through the Institutions, rather as the Boers accepted the Union of South Africa's constitution in order to subvert it. Call it a virtual guerrilla strategy if you like.
This post is also about the way history shapes itself. At the end of the Boer War, the British government launched a period of Reconstruction under Lord Milner's military administration, until the Liberal government in 1906 declared its Magnanimous Gesture of setting up a new, (relatively) democratic constitution. The Peninsular war prefigures so well the Maoist doctrine of revolutionary war that it can hardly have been an accident.