(in the US) the leaders of the armed forces who advise the President on military mattersCultureThe Joint Chiefs of Staff form a US government committee which includes the Chiefs of Staff of the US Army, Navy and Air Force, the Commandant of the US Marine Corps, and the Chief of the National Guard Bureau. It was established in 1942 and advises the US President, the National Security Council and the Secretary of Defense. In 1989, General Colin Powell became the first African American to be the committee's chairperson(= person in charge of meetings).
