Although Woodrow Wilson came to the Paris Peace Conference with high ideals the other leaders had more practical concerns. Why do you think so?
They had suffered and seen more of that war than we ever had. They accepted our help and were glad we showed up, but the idea that they could be expected to sit at the peace table full of sweetness and light having seen an entire generation of young men gunned down amidst trenches by German machine guns and artillery was too vivid and painful a memory for them to be idealists. Plus, the negotiators on behalf of Britain and France would have to answer to war weary voters back home who wanted a clear and satisfying end to the war, with the benefits that came with it.
Other European leaders had been struggling with each other for centuries. The war had simply intensified the hatred of the French towards the Germans and between many other ethnic groups. The motivation for the European Allied leaders was revenge, not preventing another war. They needed money to pay off their war debts and felt Germany and Austria should bear the brunt of these debts. Thus, Germany and Austria not only lost lands to the Allied forces, but they were also saddled with tremendous debt that crippled the German economy. Germans blamed their leaders for signing a treaty that treated them so harshly and that set the stage for Adolph Hitler's rise to power.