The Geography of American Power

The United States is a secure power. Situated in a hemispheric citadel, and protected by wide oceans, the U.S. could comfortably withdraw from being the arbiter of the geopolitical fate of Eurasia and still enjoy a significant margin of security. Such a U.S. could still project power around the globe. However, it would do so selectively, in the pursuit of narrowly defined interests and objectives. It would need few, if any, allies.  It would remain a powerful global economic actor—fuelled by a massive domestic market, deep private wealth, leading edge innovation, and high population growth.

If the U.S. was not willing to accept its own subordination, it would have to continue to engage ‘forward’ in the affairs of Eurasia, including by way leveraging the significant economic and military resources of the European Union, Britain, Japan, India, Australia, South Korea, Canada, and others to contain the emergence of such a hegemonic power.

This would be a sound geopolitical strategy. Geopolitics is the intersection of geography and power. It is concerned with questions of world order, national power, and coalitions of power. Separately, and irrespectively of whether or not the U.S. continues to engage ‘forward’, there is a related geostrategic issue that confronts Washington. Geostrategy is the intersection of geography and capability, and especially military power. Whether the U.S. withdraws, or continues to lean forward, it must build a sea-air barrier around Eurasia. It has to do so for its own defence and security, and in order to project power into, and around, Eurasia, should it have to do so.

In order to explain the idea of such a sea-air barrier, we need to start with a map.  Specifically, the map projection that U.S. geographer Richard Edes Harrison made famous in 1942, which is known as the ‘One World, One War’ map. Harrison argued that on the traditional Mercator projection of the world, the U.S. appeared to be isolated from the two major wartime strategic theatres of Europe and Asia. Harrison argued that while the Mercator projection was useful in the age of sail and steam, with the advent of air power, an ‘azimuthal equidistant projection’, pivoted around the North Pole, was required to better depict the strategic position of the U.S. in the 1940s. Such a spherical conception of the Earth, viewed from above the North Pole, would better reveal the strong points, the sea areas, and the lines of approach that the U.S. would have to secure and protect for its own defence, as well as for broader strategic purposes. With the coming of the missile age in the 1950s, Harrison’s theories were proven correct.

At the same time as Harrison was working on his maps, Nicolas J. Spykman was coming to similar conclusions, which he laid out in his last book, The Geography of the Peace, in 1944. For Spykman, the geography of Eurasia and the Western Hemisphere was the engine room of history. He argued that history was the eternal process of great powers clashing with one another in the rimlands of Eurasia—that is, Europe, the Middle East, the Indian sub-continent, East Asia, and the littoral ‘inner seas’ of the Mediterranean, the South China Sea, the Philippine Sea, and the East China Sea. The recurring question for U.S. strategy would always be the same—how to control the rimlands and littoral seas of Eurasia, in order to contain and, if necessary, defeat emerging powers, and whether to do so from afar, or in close?

Adapting this thinking, we can today describe a modern sea-air barrier around Eurasia as a series of strong points and areas of control that trace a line around these contested areas. Control of this barrier would allow the U.S. to protect itself from approaching threats, and to more securely project power, whether in its own defence, or for broader purposes, such as protecting its allies.

What line would such a sea-air barrier follow? Starting along the length of Canada’s Arctic coast, the line would run through Greenland, Iceland, the Faroe Islands (which belong to Denmark), and Scotland, an area that forms the ‘GIUK Gap’ (to use its Cold War title).  The U.S. needs to control the GIUK Gap, and have access to Svalbard (which belongs to Norway), in order to contain the threat of Russian sea power in the Atlantic.  From Britain, the line would run to Gibraltar and then to the British bases in Cyprus, so that the U.S. could access the Mediterranean and protect the northern end of the Suez Canal. Through the canal, the line would run through the Red Sea to Diego Garcia, which is the most important U.S. strategic base in the Indian Ocean, vital for projecting power into the Middle East, Central Asia, and eastern Africa.

From there the line would run to Cocos (Keeling) and Christmas Islands, which are Australian offshore territories.  The line would then run through Exmouth, Darwin, and Townsville (which are all in Australia), up to Manus Island in Papua New Guinea, and then to Guam and other key U.S. island territories in the Pacific, as well as the U.S. state of Hawaii.  Finally, the line would run along the Aleutian chain, and then through the U.S. state of Alaska proper, and before linking with the starting point of the line, Canada’s Arctic coast.

From the security of this barrier, the U.S. could project power and protect its approaches, especially in the North Atlantic, the Pacific, and the Arctic Ocean, protect its trade routes and its undersea infrastructure, secure itself in relation to space warfare and missile attack, launch military operations in Europe, the Middle East, Central Asia and Africa, rescue its citizens, and strike at its adversaries.

Control of the barrier would require the sustainment of a few trusted relationships, especially with Canada, Britain, and Australia (which would become the CAUKUS grouping), and with Norway and Denmark. The barrier would be built upon a global network of key points of presence, and would not require the U.S. to hold significant amounts of territory, or maintain an extensive network of expensive overseas bases. Coupled with its nuclear forces, and its space and cyber defences, the barrier would render the U.S. virtually invulnerable, outside of a massive, planet-destroying nuclear strike, which would also see the attacker destroyed.

Australia’s geography is an integral part of the barrier, as it provides a vital base for U.S. operations around the rimlands and littoral waters of southeastern Eurasia, and a swing point for power projection from the Pacific Ocean into the Indian Ocean. The immense value of Australia’s strategic geography is better appreciated in Washington and Beijing than it is in Canberra. In any U.S.-China military conflict, PLA strikes would be conducted against Australian bases and facilities, including in the southern parts of Australia, the latter of which would provide depth and security for U.S.-led coalition operations in the Indo-Pacific region. The recent PLAN task group mission to waters off Australia would have had as its principal military operational objective the conduct of land attack rehearsal activities, targeting bases, facilities, and infrastructure across Australia.

The Western Hemisphere is also crucial for the U.S. from a geostrategic point of view.  Even with the sea-air barrier in place, the U.S. would not be fully secure were Mexico, the Caribbean (especially Cuba), Central America, the Panama Canal zone, northern South America (especially Venezuela), and Brazil to be in various states of dysfunctionality, or were they to be actively hostile to the U.S., perhaps to the extent of hosting significant Russian or Chinese forces, or both. Further south, the Falkland Islands are critically located for sea control in the South Atlantic, should the Panama Canal become inoperable. Hemispheric defence on the near side of the sea-air barrier would therefore remain an important task for the U.S..

Whether the U.S. remains forward, or it consolidates itself in its citadel, it has to secure this sea-air barrier.  Being forward makes more sense, as it allows the U.S. to create more favourable strategic positions of strength, to the benefit of U.S. trade, technology, and investment, and for its own security and defence. Being forward is in the interests of the U.S.. However, being forward means that the U.S. has to rely on more partners, most of whom have not been willing, until recently at least, to take on a greater share of the common burden of defence and security. Most have instead preferred to expand social benefits for their own citizens, and pursue economic development, while selfishly consuming U.S. security.

Put another way, the U.S. would be more secure if it were able to control the rimlands and littorals of Eurasia on the far side of its protective oceans—in places such as Japan, Taiwan, The Philippines, Indonesia, Singapore, Malaysia, Thailand, India, the Gulf States, Saudi Arabia, Turkey, Poland, Ukraine, the Baltics, and the Nordic countries. However, such a grand strategy would require constant alliance management, and a willingness on the part of U.S. allies and partners to be prepared to significantly enhance their military capabilities, and to do more to counter the emergence of a hegemonic power in Eurasia. Were the U.S. to decide one day that it could effectively secure itself behind its sea-air barrier, withdraw from Eurasia’s contested zones, and partner with a handful of geostrategically critical allies, many of these beneficiaries of U.S. security would long for the glory days of U.S. primacy and preponderance.

Michael Pezzullo is a former deputy secretary of defence and was secretary of home affairs until November 2023.

This article appeared originally at The Strategist (ASPI).