Spending Smarter, Not More

There are three ways to reduce US defense spending.

A recent Congressional Budget Office (CBO) report examines what a $1 trillion reduction in defense spending would do to US military forces and acquisition programs over the next decade. As the report notes, reductions in the military budget do not come without cutbacks in capabilities. Such actions, though, may be a positive sign. This is simply an exercise, but it does demonstrate that budget cuts would force policymakers to create clear goals that meet ambition with practicality.

The 2017 National Security Strategy (NSS) both demonstrates and explains the folly in current defense spending. This NSS focuses on military overmatch. Military overmatch — or the idea that the US should have capabilities in enough scale to prevent military actions from any potential adversary — is not a strategy with clearly defined ends. Instead, military overmatch is the last grasp of a primacy strategy. More significantly, military overmatch has not helped counter terrorism in the Middle East, and has instead created an environment conducive to unstabilizing arms races. Similarly, in East Asia, the concept of “military overmatch” has done nothing to prevent North Korea from denuclearizing nor has it allowed the US to effectively balance against China.


The CBO report provides alternatives to this NSS’s idea of overmatch by showing three different ways to reduce defense spending. In the first option, the US would continue to achieve a version of military overmatch, but in a cheaper way. Rather than preventing all adversary military action through superiority, the CBO’s first option forces the US to identify a limited number of main strategic threats, such as strengthening coalitions and concentrating the majority of troops near strong adversaries like Russia and China. According to Option One, the new US force would contain 19% fewer active military personnel. Washington, therefore, would concentrate forces in only the most important locations. There are two main limits to this option. First, fewer troops reduce the ability for rapid response. This could allow an adversary, such as China and Russia, to make too many tactical gains early in a conflict for Washington to overcome. Second, the US will have to assess its most pertinent threats, which may result in the US not only having a small force in one location, but less forces or no forces in other locations, potentially creating power vacuums that would again put the US at a disadvantage. 

The most important takeaway from the CBO report is this: By determining what goals it wants to prioritize, it is possible to reduce US defense spending.

The second option focuses on reducing ground troops in exchange for stronger coalitions. In this option, prioritizing true adversaries remains important. This strategy attempts to deter those adversaries by forming large partnerships with countries located in an adversary’s region, but far enough away to avoid attack. The focus then becomes working with allies to deter via threatening unacceptable punishment. The US has already implemented this second option during the Cold War to counter the Soviet Union’s formation of the Warsaw Pact. In today’s world, Option Two would mean that countries alongside the US will be able to enact things like naval blockades to crush an adversary’s economy, resulting in fewer US ground troops but stationing more reserves and military equipment on allied soil. 

The main challenge with Option Two is that it requires a greater defense burden from each ally, while simultaneously reducing US global commitments. Promising a collective coalition to handle any threat sounds ideal. It would be a greater deterrent than one where the US acts as the primary defender for every ally. Nonetheless, in this option, allies may fear greater risks of US abandonment because of less US ground troops to guarantee a rapid response. If defense spending is not geared specifically toward helping allies defend themselves without forward-deployed US troops, a strategy designed to strengthen military coalitions would, paradoxically, result in weaker coalitions. The US military then will need to focus on faster, smaller weapons and units as well as long-range weapons that can protect allies from a distance. The debate on whether or not the US should reduce its troops on the Korean peninsula captures this dilemma well.  

Finally, the CBO report’s third option emphasizes a US defense posture designed to maintain “command of the commons” and military restraint by relying more on naval resources than ground ones. A command of the commons would focus on free flow of commerce and communications and allow the US to have more control over maritime trade routes and flows. Hence, a US “command of the commons”-focused force would deter adversaries by threat of economic coercion and punishment. This attempts to address the main challenge in the second option via a more extreme US position where  allies must defend and deter regional threats and aggression by themselves while receiving only some help from US combat forces. US military power would, therefore, be focused on command of the commons and protecting its own territory. The obvious risk in this option is a reduction in American influence. Without the US guaranteeing their security, current allies may seek to bandwagon with adversaries or attempt to become rival powers themselves. If this happens too much, then Washington will have to spend more money than available to control the commons. Therefore, the US must invest in naval capabilities designed to control trade as well as reducing spending on things like large battleships that do not help control trade routes.


All options have strengths and weaknesses. The first option provides the US with the most military flexibility, but also requires the narrowest definition of threats to US security. The second option somewhat reduces US military flexibility compared to the first option, but also provides for a US military that can perfect coalition warfare and respond to a wider variety of threats. Finally, the third option contains the most limited military goal: Guaranteeing command of the commons. As a result, the war-fighting capability in Option Three would be the most limited. If it is effective, the US would be able to reduce the threat of war while also maximizing its own security.

The most important takeaway from the CBO report is this: By determining what goals it wants to prioritize, it is possible to reduce US defense spending. Accepting the associated costs requires strategic thinking, something that is currently absent from recent US defense planning. Instead of focusing on how to be the most powerful country, the CBO’s exercise shows how a change in defense spending can help Washington evaluate how to be the most secure. 

Jordan Cohen is a Policy Analyst in Defense and Foreign Policy Studies at the Cato Institute and a PhD candidate in political science at the Schar School of Policy and Government at George Mason University.