Basics

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Overview

The National Defense Authorization Act (NDAA) is one of the most important pieces of legislation in the United States. It shapes the direction of U.S. defense policy, military spending, and national security priorities. Passed annually since 1961, the NDAA authorizes appropriations and outlines policies for the Department of Defense and other national security programs. As the cornerstone of U.S. defense budgeting, the NDAA addresses issues such as military pay, benefits, procurement of weapons systems, research and development, and foreign policy strategies.

This Basic will explain the NDAA, its legislative process, and issues typically included in the legislation.

What is the NDAA?

Congress passes the National Defense Authorization Act (NDAA) to provide appropriations for the funding of defense-related activities, including the Department of Defense (DOD) and nuclear weapon programs within the Department of Energy (DOE).

The bill authorizes spending limits for defense programs, setting the framework for actual appropriations through separate legislation. It establishes the legal groundwork for military policies, detailing how the armed services should operate, manage personnel, and acquire equipment. Additionally, the NDAA includes provisions on cybersecurity, space security, foreign military operations, and defense diplomacy. It often features mandates reflecting overarching defense priorities, such as servicemember quality of life, force modernization, or responses to geopolitical challenges. While the NDAA does not directly allocate funds, it grants the legal authority for DOD and DOE to utilize their budgets, which must be funded through subsequent appropriations bills passed by Congress.

The legislation passes with bipartisan votes almost every year. Fiscal Year 2024 marked the 63rd consecutive year Congress has passed an NDAA to fund American defenses. Because of its consistent ability to pass into law, the House Armed Services Committee and the Senate Armed Services Committee often use the NDAA as a vehicle to pass other pieces of legislation. 

NDAA Process

Each year, the process to craft the NDAA begins when the President submits a budget request around the first Monday of February. The House Armed Services Committee (HASC) and the Senate Armed Services Committee (SASC) then begin a series of hearings with testimony from DOD leadership and other security agencies. The Armed Services Committees draft and mark up their separate versions of the NDAA in each chamber. Like most other bills, during this process, committee members propose amendments, debate provisions, and adjust the bill based on stakeholder recommendations. After the committee markup, the NDAA is brought to the floor of each chamber for debate. The House and Senate typically propose different versions of the bill, reflecting varying priorities between the chambers. Members of Congress can propose additional amendments during this stage, with final passage in each chamber requiring a majority vote. 

Because the House and Senate often pass different versions of the NDAA, a conference committee is formed to reconcile the differences. This bipartisan committee negotiates and merges the two versions of the bill into a final, unified piece of legislation. This compromise bill is then returned to both chambers for a final vote. Once the House and Senate pass the unified version of the NDAA, the bill is sent to the President for approval. 

Upcoming NDAA & Key Issues

The NDAA is passed annually, and each year’s version reflects evolving defense priorities and national security challenges. Several key issues are expected to shape the upcoming NDAA for Fiscal Year 2025, including improving service members’ quality of life, readiness, deterrence, procurement, innovation, border security, oversight and accountability, and budgets and savings.  

Recruitment and retention of service members remains an essential issue for the DOD, and the NDAA aims to address areas creating obstacles. The NDAA determines the pay for military members and can be used to allocate pay raises. Parts of the legislation provide for benefits and personnel policy reforms. Alongside service members, the NDAA allocates benefits and resources for their families, including education, childcare, support for spouses looking for employment, and improving housing. Acknowledging the sacrifices military families make allows the NDAA to better account for the quality of life for service members.  

The NDAA ensures the armed forces are well-funded, equipped, and prepared to respond to emerging threats through its comprehensive provisions. It authorizes essential funding for advanced technologies, modern equipment, and training programs, which enhance the military’s capability to deter potential adversaries and maintain strategic superiority. By establishing clear defense priorities and allocating resources effectively, the NDAA can support the development of cutting-edge defense systems and operational readiness, ensuring the U.S. can project strength and resilience on a global scale. This legislative framework bolsters the military’s preparedness to counteract various threats and reinforces a credible defense posture that can prevent conflicts and safeguard national security interests.

The NDAA budgets for advanced technologies and innovative projects to enhance military capabilities and address emerging threats. It often incentivizes collaboration between DOD and private industry, including startups and technology firms, accelerating the development and deployment of new solutions. By prioritizing investment in breakthrough technologies such as artificial intelligence, cybersecurity, biotechnology, and next-generation defense systems, the NDAA ensures the U.S. maintains a technological edge and adapts to rapidly evolving challenges, reinforcing national security and strategic advantage.

While these investments are essential for defense and deterrence, they come at a price. The U.S. spent $820 billion on national defense in Fiscal Year 2023. The proposed House and Senate versions of the Fiscal Year 2025 NDAA allocate $883.7 billion. As Congress debates the defense budget for the year ahead, critics often disapprove of the amount of money used for defense activities and cite the amount of resources allocated for defense compared to nations with similar capabilities. The U.S. spends more on defense than the following nine countries combined; American spending accounted for nearly 40% of global defense expenditures in 2023. Advocates for a large defense budget argue providing for extensive domestic and overseas presence requires the resources to remain effective. While the raw number remains relatively large, some believe the focus should be on using funds more efficiently without necessarily increasing spending. Additionally, the Congressional Budget Office projects a decline in defense spending as a share of gross domestic product (GDP) over the coming years.

The process by which Congress creates the NDAA allows for greater oversight and accountability of the agencies responsible for the national defense. Transparency in defense spending and operations allows for rigorous examination of military programs and expenditures, enabling lawmakers to identify and address inefficiencies, prevent waste, and ensure defense resources are used effectively and ethically. Additionally, the NDAA often includes provisions that mandate independent audits and assessments, further reinforcing mechanisms for accountability and guaranteeing defense activities align with national security objectives and public interests.

These pieces combined make the NDAA a vital piece of legislation, ensuring the U.S. military remains prepared, resilient, and responsive to various challenges. As the 21st century presents new and evolving threats, upcoming NDAA legislation must balance investments in modernization, national security imperatives, and fiscal discipline. With cybersecurity, technological advancement, and climate change at the forefront of future defense policy, the NDAA will continue to shape the U.S. defense landscape and its approach to global leadership.

Effective policymaking and robust oversight through the NDAA will be crucial in sustaining the U.S. military’s strategic advantage and ensuring the defense priorities align with national and international security goals.