For much of the 19th century, Americans thought that the broad expanses of the Atlantic and Pacific Oceans protected our homeland from enemy attack. They believed that the United States was blessed with what historian C. Vann Woodward dubbed “free security.” As he noted:
Throughout most of its history the United States has enjoyed a remarkable degree of military security, physical security from hostile attack and invasion. This security was not only remarkably effective, but it was relatively free. Free security was based on nature’s gift of three vast bodies of water interposed between this country and any other power that might constitute a serious menace to its safety. There was not only the Atlantic to the east and the Pacific to the west, but a third body of water, considered so impenetrable as to make us virtually unaware of its importance, the Arctic Ocean and its great ice cap to the north. The security thus provided was free in the sense that it was enjoyed as a bounty of nature in place of the elaborate and costly chains of fortifications and even more expensive armies and navies that took a heavy toll of the treasuries of less fortunate countries and placed severe tax burdens upon the backs of their people.
Many historians took issue with the notion that the relative security that the U.S. enjoyed was free, noting that for the bulk of the century after the War of 1812, the U.S. sheltered behind the implicit protection of the British Royal Navy. That fact notwithstanding, Woodward was certainly correct about prevailing American views. Most political leaders and much of the public believed that forward presence was not needed to be safe in our own hemisphere.
In the first half of the 20th century, we learned that allowing hostile aggressive powers to dominate Europe and the Pacific Ocean littoral created significant dangers to our security, even if they seemed far away. The experience of World War II convinced most members of America’s national security elite that the future defense of the United States would have to begin well beyond the nation’s continental frontiers. As historian Michael Sherry concluded in 1987 in his pioneering study of American air power, policymakers came to believe that “American weakness had encouraged Axis ambitions in the 1930s” and that as a result “powerful military forces could deter or subdue future troublemakers.” Pearl Harbor and the new weapons developed subsequent to it demonstrated the nation’s nakedness to sudden attack and its need for unprecedented forces-in-being to ward off the coming blitzkrieg.” The result was a consensus that America’s national security in the future would require forward defense, the ability to project power to Europe, East Asia and the Middle East which, in turn, would require allies and partners around the world to sustain a globe-girdling system of bases and facilities.
In the second half of the 20th century the development of long-range aircraft, intercontinental ballistic missiles, and nuclear weapons underscored that overseas developments can directly threaten the U.S. homeland. We finally recognized that to defend the United States we must engage overseas to prevent future wars—which might ultimately involve us—from starting. The alliances we have built over the last 70 years offer the best possible means to discourage potential aggressors from starting local wars that will inevitably become global. They allow us to maintain the global commons—including freedom of the seas—across which worldwide commerce flows, creating the unprecedented increase in wealth and prosperity that has developed since World War II. The ability to provide defense in depth and rapidly project power forward to regions of concern became the fundamental basis of America’s unique global role.
Today the United States is facing two highly dangerous, aggressive, autocratic, and expansionist foreign leaders. Yet despite the traditional emphasis on forward defense and the importance of U.S. bases as a form of reassurance for allies there have been persistent calls from the Trump administration for reductions of the U.S. overseas presence.
“Our presence sends the signal that the U.S. is committed to and can prevent a fait accompli. It also can also provide opportunities for training and improving interoperability with allies, strengthening deterrence by conveying to potential adversaries that they will face a powerful counter coalition if they choose to pursue aggression.”
Vladimir Putin, who famously declared that the breakup of the USSR was the greatest geopolitical tragedy of the 20th century, has been pursuing the reconstitution of the Soviet empire since he took power. His forces occupy parts of Georgia and Moldova; he has taken Crimea; three years ago, he began a bloody and merciless full-scale war to conquer Ukraine. He has made clear that Estonia, Lithuania, and Latvia are in his sights. And he covets the recreation of a buffer zone to Russia’s west along the lines of the defunct Warsaw Pact, a sphere of influence which would allow him to dominate Poland, Hungary, the Czech Republic, Slovakia, and Romania. In addition, his regime has declared the NATO alliance to be Russia’s enemy, routinely threatens the use of Russian nuclear weapons in response to policies he opposes, and has been carrying out a clandestine campaign of sabotage against Western communications cables, armaments factories and warehouses, and transportation grids.
Half a world away, Xi Jinping, under a similar belief that China has been denied a leading role in the world by “the West,” seeks to create a de facto empire that dominates the Asia-Pacific region. His regime has declared that the South China Sea, a key waterway through which one-third of global maritime trade flows, should be declared “an internal Chinese lake,” subject to control by Beijing. China also seeks to control the two key chokepoints, the Malacca and Lombok Straits, that offer access to the South China Sea from the west. Xi has made clear his intention of reunifying China with Taiwan, with force if he cannot achieve it by coercion. The Beijing regime has, further, claimed parts of the exclusive economic zones of several of its neighbors and has used armed force to protect Chinese commercial activity in those areas.
Ominously, both Russia and China are expanding their intercontinental and particularly their regional nuclear forces. And both have demonstrated a complete and total disregard for any treaties or obligations they might have undertaken.
Should either Putin or Xi believe they can take their neighbors’ territory without suffering significant cost, they might attempt to do so. The result, an imbalance in global power, a possible denial of U.S. access to areas of the world vital to us, and an invitation for further aggression could result in war, including possibly the use of nuclear weapons—all of which could have catastrophic effects on our own security.
It becomes imperative, therefore, to make clear to both Putin and Xi that the cost of such attacks would be prohibitive, that they would significantly exceed any gains they might hope to make. Only the United States can provide the military capability to make such a threat. And we can only do so credibly if we are present in those regions. While there are costs involved in forward presence, they pale in comparison to the costs of the likely global war that would result if deterrence failed. The recent bipartisan report of the NDS Commission estimates that a global war that began in the Indo-Pacific could cost the global economy as much as $10 trillion—and that is probably an underestimate.
All this said, it is worth raising the question of what benefits, precisely, the U.S. derives from what some have quantified as a $55 billion to $80 billion annual expense. Many so-called realists who seek to diminish the U.S. presence overseas, in order to reduce defense spending and avoid foreign entanglements that might lead to “endless wars,” never acknowledge that host nations provide support and some compensation for U.S. bases, but it is still worth reminding ourselves of the non-monetary compensation the U.S. gets from its overseas presence.
Base access enables us to deploy forces forward. Repeated studies by the RAND Corporation have demonstrated that the presence of significant U.S. military forces reduces the likelihood of major interstate conflict or escalation of local conflicts into major war. Our presence sends the signal that the U.S. is committed to and can prevent a fait accompli. It also can also provide opportunities for training and improving interoperability with allies, strengthening deterrence by conveying to potential adversaries that they will face a powerful counter coalition if they choose to pursue aggression. Reassurance of allies is a particularly important and underappreciated element of U.S. base presence overseas. U.S. bases are a visible sign of U.S. commitment and willingness to extend U.S. military deterrent power to friends and allies.
The U.S. presence can also block adversaries from seeking precisely the advantages described above for themselves by arranging for access or basing themselves. The small U.S. deployment in Syria, for example, has both helped keep a lid on a resurgence of ISIS terrorism and provided U.S. overwatch of Iranian efforts to rebuild its proxy network that Israel has done so much to weaken over the last few years. When the U.S. ignores a region or vacates its positions there, we can be sure that our adversaries will seek to move in. One can already see the PRC seeking precisely these kinds of access and advantages in places where the U.S. has been chronically inattentive like Latin America, Africa, and especially the South Pacific.
The bottom line is that while U.S. forward deployed forces, in concert with and assisted by the military forces of our allies, defend allied territory—the first targets of potential aggression—they also provide a jumping off point for U.S. forces in case deterrence fails in any major contingency. The record shows that their very existence helps to prevent war and the catastrophic consequences that would engulf us too were a global conflict to break out. In doing so they also protect the American homeland. And that makes our bases and forward presence a bargain when compared to the alternative.
