What is the title of the Secretary of Defense in the Navy's Chain of Command?

The title of the Secretary of Defense in the Navy's Chain of Command typically refers to an individual who holds the position, and historically, one notable individual who served in that capacity was Chuck Hagel. His tenure supports the idea that this role is a significant part of the command structure overseeing all branches of the military, including the Navy. In the context of the chain of command, this position is critical for establishing policies and directing military operations at the highest level.

The roles of Admiral, Secretary of the Navy, and Master Chief Petty Officer of the Navy fall into different categories within the Navy's organizational structure, each with distinct responsibilities and ranks, but they do not represent the title of the Secretary of Defense. The Secretary of Defense ultimately governs the defense policy of the entire U.S. military, making this choice accurate for the question posed.