What impact did Progressivism make in U.S. foreign policy?

Progressivism did not have as much impact on American
foreign policy as one might expect.  Two of the three presidents who are seen as
progressives did not have particularly progressive foreign policies.  The third, Woodrow
Wilson, did push much more strongly for progressive ideals in US foreign
policy.

Both Theodore Roosevelt and William Taft pursued
foreign policies that were not particularly progressive.  TR was a staunch supporter of
imperialism.  He issued the "Roosevelt Corollary to the Monroe Doctrine," claiming the
right to intervene in the affairs of Latin American countries whenever the US's
interests were affected.  His "big stick diplomacy" and Taft's "dollar diplomacy" were
aimed solely at increasing US power.

By contrast, Wilson
wanted US foreign policy to try to make the world a better, less greedy place.  This is
in line with the progressives' ideas.  This shows up most clearly in Wilson's proposed
14 Points for the end of WWI.  Wilson wanted, for example, to create the League of
Nations.  By doing so, he hoped to keep the strong countries of the world from
exploiting the weak.

All in all, progressivism did not have
that much impact on US foreign policy until Wilson's presidency.