On January 1, 1942, 26 allied nations signed the Declaration of United Nations against fascism and reaffirming human rights. In 1945, after the United Nations defeated fascists in Europe and the Pacific, US President Harry Truman from the Democratic Party appointed Vermont Senator Warren Austin from the Republican Party to serve as the United States ambassador to the United Nations Conference on International Organization in San Francisco.
In addition, Truman's Secretary of State recruited 14 USA Civil Society organization members, including Rotary and Lions Club members. The Rotary and Lions Club members from around the world made two major contributions to the UN Charter. The first was to change the UN Charter's Preamble opening sentence from "We the Members States of the United Nations" to "We the People of the United Nations." The second was to give themselves a seat at the United Nations by creating the Economic and Social Council, where 80% of the United Nations' humanitarian work is done. Three years later, in 1948, Ambassador Austin cast the YES vote for the United States when meeting in Paris, France. Here's the Preamble language:
The UN General Assembly Proclaimed on December 10, 1948
"Universal Declaration of Human Rights as a common standard of achievement for all peoples and all nations, to the end that every individual and every organ of society, keeping this Declaration constantly in mind shall strive by teaching and education to promote respect for these rights and freedoms and by progressive measures, national and international, to secure their universal and effective recognition and observance, both among the peoples of Member States themselves and among the peoples of territories under their jurisdiction." - Preamble Proclamation of the Universal Declaration of Human Rights - https://proempathy.us/espdfudhr