I would differ from you analysis by raising these points: 1- Germany, like Italy, became a unified, coherent European country late in the game, which is why both countries tried to get in on the imperialist bandwagon in Africa and even the Americas. 2- As it was explained to me by my 1950s history textbook, Britain had the most powerful navy in the world, Germany the most powerful army on the continent. Germany, as was its right, tried to develop a navy, which freaked out Britain. (Check out the book "Dreadnaught, which I believe describes some of this); 3- one of the theories of the appeal of Hitler was that the allies *did* treat Germany like a mad dog and put it down, requiring the country to take blame for the war and imposing terrible conditions in the peace.
My theory is that the greatest crime of the last century was WWI. It was an exercise in colossal stupidity that devoured much of the youth of Europe and left the world with Hitler and Stalin for dessert. The idiocy of the letters between Nicky (Russia) and Willie (Germany) is a great starting point. One of the best movies on the topic (stupidity) is Kubrick's Paths of Glory, which contains one of the most moving scenes in film at the end. Check it out.