A week ago, President Donald Trump was threatening to wipe Iran off the map: “If Iran wants to fight, that will be the official end of Iran,” he tweeted. This week, the president has seemed more moderate, reportedly complaining that National Security Adviser John Bolton has pushed the administration’s policy too far toward military action against not just Iran, but North Korea and Venezuela as well.
The president’s interest in invading foreign countries—and the list of which countries he’s threatening—seems to change from moment to moment. What’s consistent, however, is a tension at the heart of the president’s approach. Both Trump and his interlocutors present their foreign policy as geared towards maintaining American primacy. And when it comes to keeping America at superpower status, risking further military conflict while neglecting the country’s diplomatic assets is exactly the wrong approach.
Despite fears about China’s rise and Russia’s resurgence, the United States remains the most powerful country in the world by a comfortable margin, spending more on its military than the next seven countries combined. The U.S. remains the only state capable of projecting power anywhere in the world. But its military is overstretched. And the current administration’s focus on maintaining an image of American supremacy risks exacerbating this self-imposed burden, hastening American decline.
From the Ottomans to the Soviets, many world powers have paid the price for overextended militaries, waging costly wars for little or no strategic gain. This isn’t a lesson the U.S. seems to have absorbed in the post-Cold War era. Particularly in the wake of the terror attacks on September 11, 2001, the United States has pursued an increasingly militarized form of global engagement, spending trillions of dollars in the so-called war on terror. After nearly eighteen years of endless war, the country seems unwilling to act realistically, to prioritize its gravest strategic threats, to reduce its military commitments and to rebalance its foreign policy.
In 1989, Yale historian Paul Kennedy argued in his classic study of global power shifts that military overstretch has often contributed to great powers’ declines: Defense costs spiral upward as countries or empires try to retain their global reach, consolidate past gains, and modernize. By the end of the sixteenth century, for example, the Ottoman Empire—which at its zenith had ruled over millions—was stretched militarily between Crimea, Central Europe, North Africa, and Persia. The Habsburg monarchy in Europe controlled a wide network of territories, from the Netherlands to Naples, from Transylvania to Spain. But its multitude of potential battle fronts led to burgeoning defense costs in the seventeenth century. Napoleon, too, ultimately stumbled on his infamous Russian invasion, falling afoul of Russia’s harsh winter while French forces were simultaneously combatting insurgents in Spain and Portugal. And in the 1970s and 1980s, the Soviet Union was stuck in foreign entanglements—including Afghanistan—while straining to keep up in a global arms race, both factoring into its demise.
As the Cold War ended, the United States was unmatched in economic and military strength. American conventional wisdom held that the dissolution of the Soviet Union marked the triumph of liberal democracy, eternally resolving the global struggle between ideologies. The U.S. was left unchallenged, unconstrained by a military or geopolitical foe. In the following decade, the U.S. championed the spread of democracy and increased its interventions into other countries and conflicts, partially in response to humanitarian concerns. It pushed Iraq out of Kuwait (in a war that, in retrospect, was refreshingly limited in its ambitions), intervened in Somalia and Haiti, backed NATO forces in Bosnia, and led the air campaign against Serbia, supporting Kosovo.
But the nature and scope of U.S. intervention changed after al-Qaeda’s terrorist attacks in 2001. Tossing aside any Cold War-style policy of containment, President Bush decided to preemptively attack potential threats. The United States invaded Afghanistan with unclear policy objectives and was soon distracted by Iraq, bungling nation building and missing early opportunities to negotiate with elements of the Taliban. The Iraq war, far from securing strategic interests by preventing an autocrat from using weapons of mass destruction, empowered Iran and contributed to Islamic State’s rise.
After spending $6 trillion fighting the war on terror, the United States is still mired in Afghanistan—the longest war in U.S. history—and struggling to get out of Iraq and Syria. Its counterterror activities stretch across some 80 countries and U.S. special forces deployed to three in every four countries around the world in 2017. President Obama saw the fault in expensive boondoggles, but failed to sufficiently cut America’s military commitments. He authorized a half-baked surge of forces into Afghanistan, supported a feckless intervention in Libya, offered mixed messages on Syria, and fell short of pivoting to Asia.
While President Trump’s policy positions are not known for being carefully crafted, his stated interest in extracting the country from forever wars like Afghanistan and Syria actually aligns with many experts’ suggestions. Pushing NATO allies to increase their military spending also has its merits—although he is hardly the first president to suggest this. But he shows no capacity for lessening U.S. commitments in a way that minimizes the strategic losses and maximizes the gains.
Trump wants more defense spending—not less—and is pulling back from global efforts to share the costs of tackling threats like climate change, demographic shifts, and nuclear proliferation. He risks provoking a direct and uncontrollable confrontation with Iran by sending a carrier group to the Persian Gulf and ratcheting up sanctions, neglects to sufficiently stifle reckless threats of military intervention in Venezuela by his hawkish advisors, wastes defense money on the border with Mexico, and shamefully keeps backing Saudi Arabia’s imprudent war in Yemen.
Ultimately, a real program for maintaining U.S. power would involve accepting the risk of occasional security failures, rather than trying to overwhelm risk with ever-higher defense spending: There is no way for even the world’s largest economy and mightiest military to become invulnerable. The United States must identify and prioritize the greatest current and future threats to its national security rather than try to do everything, everywhere. Ineffective military interventions are siphoning off funds that could be better spent at home. They also distract the military from preparing for future wars, possibly against other great powers.
While there are downsides to pulling troops out of existing conflicts too quickly, waiting too long is counterproductive—more problems will be created than terrorists killed. The United States also does not need to spend hundreds of billions of dollars each year maintaining approximately 800 military bases in 80 countries. This is roughly double the number of countries that bases were in at the end of the Cold War, and the total amount can be reduced somewhat without severely compromising America’s ability to respond to future crises.
All of this does not mean that the United States should turn inward and disengage from the world—something the Ming dynasty in China did, arguably to its detriment. Instead, the message policymakers need to absorb is one that may seem counterintuitive: Diplomacy and development may be more effective and cheaper than military spending. A smart policy prioritizing U.S. security, like the one President Trump claims he wants, would actually involve cooperating with other countries and supporting international institutions like the UN (which the president consistently denigrates), letting these institutions do the work they are designed to do, and which the U.S. military in the long term is a poor and ineffective substitute for.
History indicates that all great powers eventually fall. And it’s far from clear that striving to maintain American dominance at all costs would be a morally advisable course even if it were a realistic one. But the United States has the power to affect the pace of change in the dynamic global balance of power and reduce the chances of a devastating war with its rivals. Everyone, the U.S. included, would benefit from that.