Department of Defense

The Department of Defense (DoD) is America’s largest government agency, headquartered at the Pentagon, with a mission to provide the military forces needed to deter war and protect national security.[1][2][3] It oversees more than 1.3 million active duty service members, 750,000 civilians, and 811,000 National Guard and Reserve personnel across 4,800 sites in over 160 countries, with an annual budget of about $841 billion.

Military Service and Careers

Explore opportunities via JROTC programs, ROTC scholarships, or service academy admissions. Serving members can pursue officer promotions, professional education, and interservice transfers. Transition with USMAP, COOL, or tuition assistance.

Readiness and Technology

DoD advances with modernization in hypersonics, drones, digital tech, and procurement like Navy ships.

Support for Members and Families

Access TRICARE, fitness programs, mental health resources, and religious accommodations.

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Dive Deeper Into Department of Defense

Defense Health Agency

The Defense Health Agency (DHA) is the U.S. Department of Defense’s joint combat support agency…

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Defense Logistics Agency

The Defense Logistics Agency (DLA) is the United States Department of Defense's primary logistics combat…

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All Articles on Department of Defense

Why U.S. Navy Ships Cost So Much and Take So Long to Build

The United States Navy, the preeminent maritime force of the modern era, is trapped in a logistical and economic paradox.…

TRICARE For Life Cataract Surgery Coverage: Costs and How It Works

TRICARE For Life (TFL), in its role as a "wraparound" payer for Medicare, covers medically necessary cataract surgery. Whether it…

How a South Korean Shipbuilder Plans to Revive American Shipbuilding

The United States possesses the world's most powerful navy, yet it faces a profound industrial crisis. The domestic shipbuilding capacity…

How the NSC, Pentagon, and State Department Shape US Foreign Policy

In American government, few decisions carry more weight than those involving foreign policy and national security. Three institutions dominate this…

Should the Department of Defense Become the Department of War Again?

Former President Donald Trump and Defense Secretary Pete Hegseth have proposed renaming the Department of Defense back to its historical…

How America Tracks Nuclear Threats

Nuclear threat evaluation isn't a single task handled by one agency. It's a massive, ongoing operation that involves dozens of…

How America Responds to Nuclear Threats

America's nuclear response system operates around the clock, combining policy, technology, alliances, and public preparedness to prevent nuclear conflict. The…

How America Plans for Nuclear War

The United States maintains one of the world's most complex nuclear planning systems. It spans everything from high-level strategy documents…