President Wilson and the public of USA was reluctant to go into WW1 however USA as a most developing country could not be stay uninterested in the war which had started in the middle of Europe, affected the whole World and probably would change it.
German (U-Boat) attacks on Merchant ships of allied countries had got reaction of USA however this was still not as big threat as convinced the USA to go into war. The main threat was the change of status quo. War started in Europe however it was affecting whole World. Probably winner side would change the status quo. So, there were two option for USA and Wilson. USA would either go into war or led the peace without victory.
Every belligerent supposed short-term war at the beginning of it, and this was very good experience for USA so going into the war was the last option. The Great Was was a long-term and devastating war where countries fight against enemies in trenches while fight against allies in diplomatic meetings, for new status quo in the World. It was about colonies and there would be vacuum in colonies at the end of the war. Winners would fill this vacuum and become more powerful with extra colonies. However, if people in these colonies have chance to decide their own fates, with little help of course, belligerents would not reach their goals with their reduced manpower, exhausted industry and cracked economy could. In other words, all of their war efforts would be for nothing. On the other hand, peace gonna be stand upon democratic rights of men. Furthermore, USA was not happy with secret agreements between countries, and it was great opportunity for breaking the monopoly of United Kingdom in international seas. Navigation should be free for all states, especially states that fall behind of United Kingdom in colonial race.
Of course these aims could not be declared like this. Wilson read 14 points in congress in 08.01.2018. All of these points are full of rights of human, peace and liberty ideals as a result in the near future it was called as Wilson Idealism.
In fact it was Wilson's and USA's opportunism.
Opportunism : “The taking of opportunities as and when they arise, regardless of planning or principle.” – Oxford Dictionary
Wilson Principes influenced German public and many minorities, colonies. However it did not work in Versailles agreement which would be cause of more bloody and devastating war, WW2. On the other hand not every colonies benefit from these principes, France and United Kingdom shared Middle East while Balkan Slavs established their own kingdom. Principes are still just useful excuses for intervention for imperial states.
As a big surprise, Wilson awarded with Nobel Peace Prize in 1919.
Principes:
I. Open covenants of peace, openly arrived at, after which there shall be no private international understandings of any kind but diplomacy shall proceed always frankly and in the public view.
II. Absolute freedom of navigation upon the seas, outside territorial waters, alike in peace and in war, except as the seas may be closed in whole or in part by international action for the enforcement of international covenants.
III. The removal, so far as possible, of all economic barriers and the establishment of an equality of trade conditions among all the nations consenting to the peace and associating themselves for its maintenance.
IV. Adequate guarantees given and taken that national armaments will be reduced to the lowest point consistent with domestic safety.
V. A free, open-minded, and absolutely impartial adjustment of all colonial claims, based upon a strict observance of the principle that in determining all such questions of sovereignty the interests of the populations concerned must have equal weight with the equitable claims of the government whose title is to be determined.
VI. The evacuation of all Russian territory and such a settlement of all questions affecting Russia as will secure the best and freest cooperation of the other nations of the world in obtaining for her an unhampered and unembarrassed opportunity for the independent determination of her own political development and national policy and assure her of a sincere welcome into the society of free nations under institutions of her own choosing; and, more than a welcome, assistance also of every kind that she may need and may herself desire. The treatment accorded Russia by her sister nations in the months to come will be the acid test of their good will, of their comprehension of her needs as distinguished from their own interests, and of their intelligent and unselfish sympathy.
VII. Belgium, the whole world will agree, must be evacuated and restored, without any attempt to limit the sovereignty which she enjoys in common with all other free nations. No other single act will serve as this will serve to restore confidence among the nations in the laws which they have themselves set and determined for the government of their relations with one another. Without this healing act the whole structure and validity of international law is forever impaired.
VIII. All French territory should be freed and the invaded portions restored, and the wrong done to France by Prussia in 1871 in the matter of Alsace-Lorraine, which has unsettled the peace of the world for nearly fifty years, should be righted, in order that peace may once more be made secure in the interest of all.
IX. A readjustment of the frontiers of Italy should be effected along clearly recognizable lines of nationality.
X. The peoples of Austria-Hungary, whose place among the nations we wish to see safeguarded and assured, should be accorded the freest opportunity of autonomous development.
XI. Rumania, Serbia, and Montenegro should be evacuated; occupied territories restored; Serbia accorded free and secure access to the sea; and the relations of the several Balkan states to one another determined by friendly counsel along historically established lines of allegiance and nationality; and international guarantees of the political and economic independence and territorial integrity of the several Balkan states should be entered into.
XII. The Turkish portions of the present Ottoman Empire should be assured a secure sovereignty, but the other nationalities which are now under Turkish rule should be assured an undoubted security of life and an absolutely unmolested opportunity of an autonomous development, and the Dardanelles should be permanently opened as a free passage to the ships and commerce of all nations under international guarantees.
XIII. An independent Polish state should be erected which should include the territories inhabited by indisputably Polish populations, which should be assured a free and secure access to the sea, and whose political and economic independence and territorial integrity should be guaranteed by international covenant.
XIV. A general association of nations must be formed under specific covenants for the purpose of affording mutual guarantees of political independence and territorial integrity to great and small states alike.