It was the refinement of the Bessemer process, first used in the United States in the 1860s, that allowed for the major advance in skyscraper construction. As steel is stronger and lighter in weight than iron, the use of a steel frame made possible the construction of truly tall buildings.
Truman implemented this in response to two threats one being a communist-led uprising against the government in Greece and two being Soviet demands for some control of Turkey's Dardanelles. It was implemented in Berlin when Truman ordered U.S. planes to fly supplies to the people of West Berlin in response to the Soviet Union's 11 month blockade on Berlin.. or something among those lines
