Quote Originally Posted by Bob
Did the victors of WWI provoke an inevitable WWII by their occupation by policy of Germany through the harsh terms of the Treaty of Versailles?
"Inevitable" is too deterministic. I think it's generally accepted that the termination conditions of WWI did not resolve all of the outstanding issues in Europe, and also created new conditions for conflict. The Great Depression had an equally (or more?) important impact on the political and economic conditions that facilitated the success of Nazism. Germany survived World War I, unlike Russia, Austria-Hungary, and the Ottoman Empire. But this question is also one with an implied structural theoretical base: did the individuals in politics and business matter at all to the outcome? And lastly, the agenda of the Nazi Party was not only the reversal of the Versailles Treaty, but also the establishment of a new German Empire in Europe itself. What about the end of WW1 prompted an imperial/colonial focus in Europe instead of Africa or Asia? Did those same conditions make it easier for the Nazis to succeed than other right-wing and left wing factions (particularly the socialists)? The Nazis were adeptly organized and by 1933 they had forged a number of key political and business alliances that propelled them to power. The other question is: was Nazi policy deliberate from start to finish, or did it evolve as the party gained power and became entangled in another world war? I forget which one, but one of the Werhmacht field marshals after the war basically started that none of them anticipated the invasion of Poland to start a global war.

Quote Originally Posted by Bob
Did the victors of the Cold War provoke an inevitable War on Terrorism and associated Arab Spring by their decision to largely leave in place in the Middle East the policies, practices and relationships nurtured during and in support of activities designed to contain the Soviet Union?
Same thoughts as above, although Islamism was already on the ascent since the final failure of the Arab nationalists in 1973. I think the end of Arab nationalism as a credible political force had more to do with the emergence of Islamism than anything else. I think globalization (proliferation of weapons, technologies, communication, etc) contributed more significantly to Islamism's successes since then.

Quote Originally Posted by Bob
Do ideologies - be it Nazism, Communism, Islamism, or any other "ism" radicalize otherwise content populations to rise in illegal conflict, or are these simply effective tunes tailored to help a particular "parade" march in step?
I think this is an important and deep question. First, ideologies don't emerge in a vacuum and it's difficult to predict which ideas will catch fire or how they will evolve over time. It's been argued that the ideological origins of Nazism can be traced to the mid 19th century. Of course, communism can be traced back to the writings of Marx in the same time period -- all before the emergence of a unified Germany, the rise of the US, and the two World Wars. How could anyone predict that these ideologies would more or less shape the second half of the 20th century? But it's also important to note that Marx himself argues that ideological reproduction is function of a system's political economy; in other words, the material system exists first and from it emerges an ideology to sustain it. In my view, this is probably the most accurate; people willingly believe what they wish to explain the world around them. The more desperate they are, the more radical the ideas will be. When times were good in the Weimar Republic, the Nazi party struggled to find support among the electorate. That changed with the Great Depression.