Final answer:
The Marshall Plan was the policy after World War II that provided economic aid to European countries for affordable housing and improving urban living conditions, to prevent the spread of Communism and facilitate economic recovery.
Step-by-step explanation:
After World War II, the policy or initiative in the United States that aimed at providing affordable housing and improving urban living conditions was the Marshall Plan. This plan, also known as the European Recovery Program, was implemented between 1948 and 1952, giving $13 billion in economic aid to European nations to assist in their rebuilding efforts post-war. It was motivated by the desire to prevent the economic disorder that often facilitated the growth of Communist parties, as well as restoring global trade, and was successful in preventing the spread of Communism and aiding the economic recovery of Western Europe.