He was a "staunch free trade advocate and disciple of Wells," and he launched a "vigorous campaign aimed at combating the protectionist sentiment that was being generated by the war in Europe.
He believed that tariff barriers were one of the leading causes of war, and that their elimination would usher in a new era of peace and economic prosperity.
"[3] A growing dispute over perceived pacifist views between League president was George Haven Putnam, who was based in New York City, and some members of the Boston group, including its secretary Kenneth B. Elliman and most of the executive committee who were based in Boston, resulted in a splitting up of the organization that led to the founding of the Free Trade League in New York in 1919 under Putnam.
"[3] Putnam served as president of the Free Trade League during the 1920s but the work was "hampered by lack of funds and dwindling public support".
Ultimately, the effects of the Great Depression and the Smoot-Hawley Tariff of 1931, however, resulted in the defeat of the free trade movement and the League "appears to have ceased its functions in 1933.