Indeed, USMC, most specifically to the Congress of Vienna that followed the Napoleonic Wars and the reshaping of Europe that came from it. The Congress System was originally instituted with the idea of solving problems by meetings and with words instead of by armies and with bullets. In many ways it worked fairly well, at least up until the Crimean War in the 1850s, but in the end, the changes made by the great powers at Vienna resulted in a slow movement toward and intricate system of alliances among the major European powers, Britain, France, Germany (after 1871, Prussia before that), Italy, Austria-Hungary, and Russia. Those alliances ultimately proved their undoing when the series of Balkan crises arose in the late 19th and early 20th centuries. Every nation seemed to have the entrenched belief that any war would indeed be decided quickly. The entire German strategy was based on the idea of a "quick" and victorious war against France (6 weeks was the projection), then a fast turn on Russia before she could mobilize. It almost worked. Virtually no one realized the havoc modern woulds would wreak, however. Your point about lessons learned from the American Civil War especially is quite apt. That was the first truly "industrialized" war with killing in wholesale lots instead of penny packets. No one listened to the lessons that were there for the taking. Many European nations sent observers to both sides of the conflict, so there is little excuse for not having heeded the lesson.