America's bases and the costs of global reach

Few countries in history have enjoyed the ability to project military power as far and as quickly as the United States. Yet the 2026 Iran war demonstrated that such reach depends on an extensive web of alliances, access agreements and overseas infrastructure extending far beyond America's borders. According to the Quincy Institute, a Washington-based think tank, the United States maintains approximately 750 military base sites across 80 foreign countries and territories, at least three times as many overseas bases as all other countries combined.

The conflict highlighted both the advantages and burdens of such a system, allowing American forces to operate across multiple theaters while exposing host countries to retaliation and threatening energy flows through the Strait of Hormuz. As tensions rise not only in the Middle East but also in the Indo-Pacific and Europe, the question facing governments is no longer simply how military power is exercised. It is whether the networks that sustain it can withstand the pressures of an era marked by greater geopolitical rivalry and growing pressure on the global commons.

Building an empire of access

At the end of World War II, few anticipated that a system of wartime installations would evolve into the largest overseas military presence in modern history. Most wartime bases were viewed as temporary necessities expected to disappear with demobilization. The onset of the Cold War, however, transformed what had been a wartime network into something far more enduring. As rivalry with the Soviet Union deepened, Washington converted much of that infrastructure into a permanent system of alliances and forward deployments stretching across Europe, East Asia and, later, the Middle East.

By the end of the twentieth century, overseas access had become central to American strategy. In a 1999 article published in the U.S. Naval Institute's Proceedings magazine, retired Vice Adm. Robert Dunn described access as the key to power projection, arguing that positioning forces abroad had become indispensable to responding to regional crises.

The logic only deepened after the 1990-91 Gulf War. Facilities in Bahrain, Qatar, Kuwait and the United Arab Emirates became pillars of American operations in the Middle East, while long-established bases in Japan, South Korea and Europe supported commitments elsewhere.

Their importance became even clearer after 2001. The Quincy Institute estimates that overseas bases supported U.S. wars and military operations in at least 25 countries between 2001 and 2021, underscoring the centrality of forward deployments.

Yet bases themselves are only part of the equation. According to a 2016 report by RAND, a U.S.-based policy research organization, overseas bases provide advantages that range from deterrence and intelligence collection to rapid deployment capabilities, but their effectiveness depends less on infrastructure itself than on the willingness of host governments to permit their use.

That distinction has become more important as geopolitical competition intensifies. Access is ultimately a political arrangement rather than a permanent entitlement, meaning military reach depends on governments whose priorities may differ from Washington's and whose willingness to accept the risks associated with hosting American forces cannot be taken for granted.

The Iran war and shared vulnerabilities

The 2026 conflict with Iran offered a reminder that foreign bases carry risks not only for the United States but also for the states that host them.

American operations depended heavily upon facilities and permissions provided by Gulf partners, even as those same countries had strong incentives to avoid being drawn into a wider confrontation. Their economies are deeply integrated with global trade, and many sought to preserve channels with Tehran while maintaining security ties with Washington.

Yet Iran made clear that geography alone would not determine who became involved in the conflict. Tehran explicitly warned that countries facilitating American operations would be treated as participants, and subsequent strikes against U.S. facilities in Qatar and Bahrain demonstrated that host countries themselves had become part of the battlespace.

The consequences extended beyond the bases themselves. Airspace, ports, energy infrastructure and commercial shipping routes across the Gulf suddenly acquired strategic significance, while governments that had hoped to remain outside the conflict found themselves balancing their security partnerships with Washington against the imperative of limiting escalation and preserving economic stability.

Beyond bases

Modern military power depends on far more than military bases alone. Ports, civilian airfields, fuel depots, telecommunications networks and commercial shipping routes all form part of the architecture that allows forces to operate at long distances.

In a 2025 analysis, National Defense University Press, the publishing arm of the U.S. National Defense University, argued that preserving operational access requires diplomatic, economic and informational efforts alongside military capabilities. The publication noted that much of America's Indo-Pacific posture still rests upon Cold War-era arrangements concentrated around Guam, Japan and South Korea, creating vulnerabilities that adversaries could exploit. The Modern War Institute at West Point echoed those concerns in June 2026, arguing that decades of operations in permissive environments encouraged assumptions that supply lines would remain secure and uninterrupted.

The Iran war demonstrated how quickly those assumptions can break down. Roughly 20 million barrels of oil per day, representing about one-fifth of global consumption, normally pass through the Strait of Hormuz. Efforts to bypass disruptions relied upon alternative pipelines, offshore transfers and maritime networks extending from Oman to the Red Sea.

The consequences extended far beyond the Gulf. European energy markets, Asian importers and global shipping companies all felt the effects of uncertainty generated around one of the world's most important maritime chokepoints. Military access and commercial access proved inseparable.

Decades of alliances, access agreements and overseas infrastructure have given the United States a level of military reach unmatched by any other state. Yet the 2026 Iran war demonstrated that global reach also creates dependencies. Access rests not only on bases, but on the political calculations of allies, the resilience of commercial infrastructure and the willingness of host countries to accept the risks associated with conflict.

For much of the post-World War II era, overseas access has been one of America's greatest strategic advantages. The events of 2026 suggested that it may also be one of its greatest vulnerabilities.