Actually when you get down to it, Lincoln creating a supreme centralized US government and destroying states rights led to the kind of power that became involved in WW1, when we entered very late to push a stalemate into the Allied victory over Germany.
What did that lead to? The treaty of Versailles, and the growth of the Nazi party. Without the US help, a more balanced Armistice would have been created, and conditions would have never been possible for the Nazis to rise to power.
That doesn't mean that something else horrible wouldn't have occurred, but the Nazis were only given fuel by the economic collapse and hyperinflation that resulted from the ridiculous reparations for WW1 (and let's face it, there were no 'good guys' in WW1, it was just a clash of greed between empires).







