The world lives in fear of the “incident”, that one event that will ignite a great conflict. The Thirty years’ War was the first great destructive conflict whose pattern was continually repeated through to WWII. In sum, it can be concluded that it is always men, and not events, which determine the fate of nations.
…In the years of the war the Dutch had seized half of the East Indies from Portugal; in the years of peace they had stolen the trade of the West indies. It was vain to hope of defeating them at sea, but a well-aimed blow by land would solve the problem. Struck in the heart, the octopus would loosen its distant tentacles. Thanks to this argument, and this support, the party of war prevailed. The truce was denounced. The half-settled troubles of Germany were swept up into a general war.
Thus we can answer our question. The Thirty Years’ War, as a general war, was not created by the German and Bohemian incidents which officially began it. These could have been settled, or at least localized, as so many other such incidents had been. Perhaps no general war arises out of mere incidents. General wars arise because the governments of great powers, or the men behind such governments, want war and exploit such incidents. In 1914 the German government did not want war, but the German general staff did. In 1939 Hitler wanted war. And in 1621, in the greatest power in Europe, behind the politicians of the peace, there was a body of men- grim, faceless officials, contemptuous of political reasons- who positively wanted war because they believed that they could win the war whereas, in a modern world, they could not win the peace.
It only remains to say that, as in 1914, as in 1939, they did not in fact win the war either. They began well, of course. They were prepared and their enemies were not. And they had chosen a good time. In the next few years the House of Hapsburg would win triumph and triumph and Spanish statesmen would dream of dominion over the Baltic and of the conquest of England. But then, slowly but effectively, the other great powers would be roused; war would reveal new forces, new techniques; once again Spain would be forced to make peace; and this time it would not be a Spanish peace: it would be the end of Spain as a great power.