US Defense Budget Trends and US Security Strategy

Abstract

With the end of the Obama administration and the emergence of the Trump administration, it is important to examine the trends in US military spending to understand future US military capabilities, military strategy, and, by extension, US global strategy. US military spending is a key element of the East Asian military order and an important factor in assessing the financial backing for President Obama's pivot to Asia strategy. President Trump, since his presidential campaign, has advocated a "peace through strength" strategy, opposing defense budget cuts and strongly advocating for enhanced capabilities such as troop numbers and weapons modernization. Overall, however, the US global intervention strategy is expected to be maintained.

Amidst the challenges and twists and turns in the budget approval process, including automatic budget sequestration, the approved defense budget of $585 billion was a product of careful consideration to minimize capability attrition and maintain superiority, while prioritizing responses to Russian activities in Ukraine, the rise of the Islamic State, the Ebola outbreak, and the growing threats of cyber security, the rise of China, and military challenges in space. The 2017 budget of $618.7 billion also identified Russia, China, North Korea, Iran, and the Islamic State as the top five US threats, and while largely similar to the previous year's budget, it allocated increased funding for responses to these threats and for developing new technologies. Specifically, it can be broken down into maintaining technological and numerical superiority in naval and air power, maximizing the mobility of ground forces, strengthening space and missile capabilities, enhancing global information and reconnaissance capabilities, and bolstering counter-terrorism warfare capabilities. In the Asia-Pacific, the strategy maintains the pivot to Asia while aiming for geographical distribution, operational capabilities, and political sustainability. With Guam as a strategic hub, the plan is to be fully prepared for China's military buildup, North Korea's threats, and contingencies in the South China Sea. The importance of this is also highlighted. Regarding the South China Sea, the Maritime Security Initiative will be implemented over the next five years to support Southeast Asian nations, with a planned budget of $425 million.

While it is premature to predict Trump's East Asia security strategy and China strategy, the core elements have remained unchanged since his inauguration. China's military buildup continues, and while the US will pursue economic recovery strategies, it will be difficult to reduce its military involvement in Asia. This is because the projection of US military power at global and regional levels offers significant benefits to the US, not only in terms of security but also economically. For now, the Trump administration may adopt a passive stance in its security strategy for economic gain, but depending on the trend of economic recovery, it may re-engage in active foreign intervention. President Trump is already discussing a "peace through strength" strategy and is ordering proactive measures against major threats and competitors such as the Islamic State, North Korea, and China. A crucial variable in South Korea's security strategy is the military balance between the US and China. The military spending and major budget allocation directions of both countries will reflect their respective strategies. Therefore, it is essential to closely monitor the trends in military spending and strategic changes of both nations and to develop strategies that maximize South Korea's national interests amidst their military competition.

Main Text

US defense spending, at 36% of global defense spending in 2015, remains overwhelming. Following the US, China, Saudi Arabia, Russia, the UK, India, France, and Japan are the next largest spenders, but the combined defense budgets of the 2nd through 9th ranked countries are still less than that of the US. South Korea ranks 10th in defense spending. In terms of defense spending growth rate, China shows the fastest growth, while in the US, voices calling for continuous defense budget reductions due to the fiscal deficit have been rising. However, in absolute terms, the US still spends more than twice as much as China on defense. While China's military spending is concentrated in the Asia-Pacific region, US defense spending incurs significant costs for conducting wars in the Middle East, and its base budget is global in scope. Therefore, when considering only East Asia, the gap in military spending between the US and China may not be as large as it appears on the surface.

After the 9/11 terrorist attacks, the base budget for defense spending rose to its highest level since the Reagan era, but the scale of military power did not increase commensurately. Although the Army and Marine Corps expanded in the late 2000s for combat operations in Iraq and Afghanistan, the overall scale of military power did not change significantly due to the reduction in naval and air forces. Instead, while maintaining the scale of military power, the budget began to decrease from 2010 onwards, leading to a pattern of budget allocation focused on acquiring technologically advanced forces for efficient military operations with a smaller military. A key principle of current US defense spending is to mitigate the increase in the budget as much as possible while focusing on securing efficient combat power and developing equipment for a smaller force.

In formulating its defense budget for 2016, the US identified three geopolitical challenges: Russian activities in Ukraine, the rise of the Islamic State, and Ebola. It also cited the growing threat of cyber security, the rise of China, and military challenges in space. Conversely, it pointed to problems in the US defense posture: 1) the technological gap the US maintains with other countries is narrowing, 2) the military readiness across all domains is declining compared to the past, 3) congressional opposition to defense reform is increasing, and 4) uncertainty regarding future resource mobilization is growing.

President Trump has consistently pledged to strengthen US defense capabilities since his presidential campaign, vowing to make the US military strong again, and defense spending increases are expected to continue. President Trump has advocated for increased defense spending in various areas, including warships, troop numbers, and nuclear weapons, and has stated his intention to accelerate the $1 trillion military modernization plan initiated by President Obama. He has announced plans to increase the Navy's fleet from the current 277 vessels to 350. The Air Force plans to increase its fighter jets from the current 1,200 by 100 more, while modernizing aging aircraft that have exceeded their 50-year service life. Troop levels are also planned to increase from the current 475,000 to 540,000, and the Marine Corps is expected to expand by 10,000 personnel to 36 battalions.

A crucial variable in South Korea's security strategy is the military balance between the US and China. The military spending and major budget allocation directions of both countries will reflect their respective strategies. Despite pressure to reduce defense spending, the US administration has strived to secure maximum budget allocation and has pursued modernization of weapons and equipment and acquisition of cutting-edge technologies to offset the trend of troop reduction. In this context, the US is developing various weapons to counter China's anti-access/area denial (A2/AD) strategy and is focusing on strengthening its naval and air power. These trends are expected to continue, and the US-China military technology gap is projected to be maintained for a considerable period. However, as China's economy develops, its military spending may continue to increase, and given that China's military strategy is primarily focused on the Asia-Pacific region, the outcome of competition with the US, which seeks to maintain global stability, remains to be seen.

Author

Professor of Political Science and International Relations, Seoul National University. Director of the Center for International Relations at the East Asia Institute (EAI). He graduated from the Department of Diplomacy at Seoul National University and received a Ph.D. in Political Science from Northwestern University in the United States. His main research areas include international political theory, diplomatic history, and studies on the ROK-US alliance and the Korean Peninsula. His major publications include "Threats of War and Peace Between North and South Korea" (2006, co-authored), "Is Politics Moral?" (2012), and "East Asian International Politics: From History to Theory" (2011).