The President's formal command authority bypasses the JCS, but in practice his decisions, or those of the Secretary of Defense acting on his behalf, are routed through them on their way to the CINC unified commands.
Inter-service rivalry is one recurring problem within the JCS, but
the most serious incident was a conflict between the JCS and civilian
leaders. It occurred in August 1967, when the Joint Chiefs threatened to
resign over civilian handling of the war in Vietnam. Sixteen years later,
with the bombing of the Marine barracks in Beirut, it was clear that the
JCS still hadn't achieved their goal of holding civilians accountable for
the use of troops abroad.
ISBN 0-395-42923-4
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