Lester B. Pearson
a Canadian statesman, diplomat and politician who won the Nobel Peace Prize in 1957. He was also the fourteenth Prime Minister of Canada from April 22, 1963, until April 20, 1968, as the head of two back-to-back minority governments following elections in 1963 and 1965.
During his time as Prime Minister, Pearson's minority government introduced universal health care, student loans, the Canada Pension Plan, the Order of Canada, and the current Canadian flag. During his tenure, Prime Minister Pearson also convened the Royal Commission on Bilingualism and Biculturalism. With these accomplishments, together with his groundbreaking work at the United Nations, and in international diplomacy, Pearson is generally considered among the most influential people of the 20th century.
In 1957, for his role in defusing the Suez Crisis through the United Nations, Pearson was awarded the Nobel Peace Prize. The selection committee claimed that Pearson had "saved the world." The United Nations Emergency Force was Pearson's creation, and he is considered the father of the modern concept of peacekeeping. His Nobel medal is on permanent display in the front lobby of the Lester B. Pearson Building, the headquarters of the Department of Foreign Affairs and International Trade in Ottawa.
Pearson never had a majority in the Canadian House of Commons, but he nevertheless managed to bring in many of Canada's major social programs, including universal health care, the Canada Pension Plan and Canada Student Loans, and established a new national flag, the Maple Leaf. His legislation included instituting the 40-hour work week, two weeks vacation time and a new minimum wage. Pearson signed the Canada-United States Automotive Agreement (or Auto Pact) in January 1965, and unemployment fell to its lowest rate in over a decade.
While in office, Pearson resisted U.S. pressure to enter the Vietnam War. Pearson spoke at Temple University in Philadelphia on April 2, 1965, while visiting the United States, and voiced his support for a negotiated settlement to the Vietnam War. When he visited U.S. President Lyndon B. Johnson the next day, Johnson (supposedly) grabbed Pearson by the lapels and shouted, "You pissed on my rug." Pearson later recounted that the meeting was acrimonious, but insisted the two parted cordially.
Pearson was also remarkable for instituting the world's first race-free immigration system, throwing out previous ones that had discriminated against certain people, such as Jews and the Chinese. His points-based system encouraged immigration to Canada, and a similar system is still in place today.
But if we're talking about the USA Strictly, my pick is Barry Goldwater.