After World War II, the United States occupied Japan, joined the North Atlantic Treaty Organization (NATO), and helped organize the United Nations. These actions show that the United States was

taking on greater global responsibility

Explanation:

The World War II took place soon after the 1st World War. It started in the year 1939 and ended in the year 1945. Soon after the 2nd world war, the United States of America occupied Japan and then joined the NATO.

NATO was formed to provide collective securities to its member nations both politically and military security from the threat of other countries, especially form the Soviet Union.

The USA also helped to form the United Nations. It is a global organization that was formed after the world war and its main purpose is to maintain peace and freedom of all the countries globally.

Thus America took on a greater global responsibility in forming various global intergovernmental organization that helped to keep peace in the world.