Herbert Hoover was in London at the beginning of World War I. He volunteered to direct the exodus of American tourists from Europe and then to head the Commission for Relief in Belgium. That position brought him public attention as the "great humanitarian." The commission fed 10 million people during the war and left funds for Belgian postwar reconstruction. In 1921, he was appointed secretary of commerce in the Harding administration.
He was concerned with applying rational principles in order to end conflict between labor and business. But, he was mostly preoccupied with trying to bring the benefits of cooperative action to business owners and farmers without destroying individual initiative. His views and policies were popular in the late 1920's. In 1928, after Calvin Coolidge announced he would not seek re-election, Hoover launched a successful presidential campaign.
The stock market crash of 1929 and the following Depression of the 1930's shattered Hoover's dreams and his popularity. He refused to mobilize fully the resources of the federal government to save the collapsing economy. Franklin D. Roosevelt easily won the 1932 election over Hoover by promising a New Deal.