In the late stage of the First World War,the US President Wilson proposed so-called Wilsonism,which was full of paradoxes.Wilson tried to solve the confrontations between the powers and their colonies through"the Principle of National Self-determination,"but he had to rely on the support of the powers such as Britain,France,Japan and Italy to realize his plan of the League of Nations.Therefore,paradoxically Wilsonism had a both contradictory and collaborative relationship with the powers.This paradox was illustrated in the treatment of the Shandong issue,in which Wilson could not achieve the balance between the morality of national self-determination and the power politics of the powers.In order to make the League of Nations come true,Wilson had to make a difficult choice between"morality"and"politics".As a result,Wilson was trapped in a mental dilemma and thus suffered from an extremely painful identity crisis.When dealing with the Shandong issue,Wilson gave up his moral promise to China for the League of Nations.For Wilson,this was a choice made at a"suffering moment".