It is possible—though far from certain—that the coming Trump presidency will herald a broad retreat from most of America’s overseas military commitments and actions. In the past, Trump has expressed his skepticism—or, perhaps better said, his irritation—over such commitments, especially to NATO. And while their apparent views are yet to be tested by actual overseas crises, J. D. Vance and Pete Hegseth, Trump’s nominee as Secretary of Defense, are both said to be disenchanted with America’s “forever wars.” 

Whether or not in the coming years there will be a turn toward “isolationism”—better termed “military non-interventionism”—there is a strong case for the gradual end of U.S. military commitments and actions outside our own country.

From 1776 through 1941, except for the U.S. entrance into World War I in 1917, the grand strategy of America was essentially that of isolationism. As set out by Washington and Jefferson, that policy was defined primarily to mean no political or military commitments to foreign countries that could embroil the United States in foreign wars that were irrelevant to our national security. As is often noted, isolationism did not entail complete withdrawal from world affairs, nor did it mean economic autarky. Indeed, even military non-interventionism was understood not to apply to “our backyard,” typically defined to mean the entire Western Hemisphere.

Isolationism permanently ended with the U.S. entry into World War II. Since then, the fundamental premise of American foreign policy has been that national security requires the maintenance of a balance of power in the major world regions. After the defeat of Imperial Japan and Nazi Germany, that goal was pursued through the policy of containment, which aimed to prevent Soviet, Chinese, or communist expansionism in Europe, Asia, and the Middle East.

The underlying logic or premise of wars fought to maintain regional balances of power has been that it is better to fight a war—even a major war—against an expansionist state or group of states sooner rather than later when they could have attained preponderant power. However, even if this logic was compelling in the past, as in WWII, particularly against the Axis powers, it is no longer. The costs of going to war now against nuclear powers—such as Russia, China, or possibly Iran in the near future—might already exceed comprehension. Alternatively, deterrence, smart diplomacy, and other instruments of statecraft might well prevent the postulated later war from ever occurring. 

There are only two ways in which the security of the United States in its homeland can be threatened: by a conventional invasion or by nuclear war. But the United States would continue to be immune from invasion even in the most extreme and barely imaginable scenarios, in which either a revived imperialist Russia came to dominate Western Europe or China somehow brought the lands, population, and resources of Asia under its control—for what could they do next, send their fleets across the Atlantic and Pacific to invade America?

To be sure, national security is not the only national interest of the  United States, for it is undeniable that we have important overseas political and economic interests that could be jeopardized by the emergence of hegemonic states in Europe, Asia, and the Middle East. Nor is it the case that all overseas U.S. military interventions have been chiefly motivated by balance of power considerations. However, those considerations have been the crucial ones when our basic security—or predominance—in the Western Hemisphere has been thought to be ultimately threatened, as in WWI, WWII, and the major conflicts with China and Russia—or their perceived “proxies”—since 1945.

Europe

There is increasing concern about the ultimate intentions of Vladimir Putin’s Russia, which, in some analyses, may go beyond Ukraine to threaten the former Soviet-dominated states of Eastern Europe. In light of the difficulties Russia has had in conquering just the eastern parts of Ukraine, the immense casualties it has suffered, and the high and increasing economic costs of its war, the feared threats of further Russian expansionism seem far-fetched.

Moreover, should such a threat develop, it is hard to see how the overall European balance of power could be overturned as long as Western Europe itself was not threatened. Still, for the sake of analysis, let us suppose that such a Russian threat really materialized, that Russia conquered Eastern Europe and then was in a position to threaten Western Europe. The fundamental issue in terms of American national security would be whether the United States should again go to war—a nuclear war, in all likelihood, at least at the level of tactical nuclear weapons—in order to preserve the European balance of power.

It is hard to see why. In the event of a radical Russian threat to the continent, the European members of NATO would not only have the nuclear deterrence of France and Britain but also the economic, geographic, and technological capabilities to mount a purely conventional defense that could defeat a Russian attack without any American participation. And if the Europeans are unwilling to pay the economic and other costs of building up their defenses and refuse to do what could conceivably be necessary to preserve their very independence, then there is little case for the United States to go to war with Russia on their behalf. Trump’s skepticism about NATO has some basis, though it seems to be largely due to the wrong reasons: his emphasis should not be on the allegedly “unfair” economic costs to the United States but rather on the risks to our national security.

The policy implication of the argument I have been making is this: the United States should announce that over the next five years, its military bases in Europe will be gradually closed, and at the end of that period, we will withdraw from NATO. That is sufficient time for the nations of Europe, collectively far stronger than Russia, to shore up their defenses.

Asia

In the past decade, driven by balance-of-power thinking, the United States has greatly expanded its military power and defense commitments in Asia. It is instructive to reflect on how and why the United States came to believe that its national security required the maintenance of a balance of power policy in Asia. It appears that this began “in a fit of absence of mind,” as nineteenth-century British imperialism was famously characterized.

In 1898, the United States “acquired” (as it is often quaintly described) the Philippines, previously a Spanish colony, as an unintended and unforeseen byproduct of the U.S. defeat of Spain in the Spanish-American War. As a result of what should be regarded as an absurd historical accident, it became an unexamined axiom that the United States—now a self-described “Pacific Power”—must maintain a balance of power in Asia in order to prevent a potentially hostile power from dominating the mainland and invading—Where? Surely not the American homeland? In fact, during the rise of Japanese expansionism in the 1930s, the primary concern of the U.S. government was over the threat to the Philippines.

In short, had we not “acquired” the Philippines, it is unlikely we would have come to think of ourselves as a “Pacific power” (as Obama and others have termed us) with the attendant need to preserve Asia’s balance of power. Consequently, this unexamined axiom led to the American intervention in the Korean War and especially the unnecessary war with China, a consequence of the Truman administration’s decision to let American armies conquer all of Korea and advance to the Chinese border, rather than settling for the re-establishment of the division of Korea after the defeat of the North Korean invasion.

Then, in an even worse tragedy, the United States went to war in Vietnam in the 1960s to prevent the communists from winning a civil war. In the process, the intervention precipitated another Chinese intervention that might have come perilously close to a full-scale Sino-American war—a war that even then might have become a nuclear one. And if balance-of-power thinking continues, there will be a growing risk that this country may stumble into its worst and most dangerous war yet against a nuclear-armed China.

Is China An Expansionist State?

Unsurprisingly, China sees itself as a defensive state legitimately alarmed by the growing U.S. military power and commitments in Asia. Consequently, China has taken a series of steps, including what we see as military “provocations,” in order to assert what it considers to be its national rights in the region.

Chinese behavior raises three issues. First, is China truly an expansionist state that seeks to establish hegemony over the entire region? Second, even if China has such intentions—or later develops them as its military and economic power continue to grow—will it have the capability of destroying the Asian balance of power? The third issue is by far the most important one in terms of U.S. national security: why should the United States be prepared to use armed force, even if that were the only way to prevent Chinese domination of Asia?

Many Chinese and regional specialists are skeptical about alarmist assessments of the Chinese threat in Asia. Rather, they argue that despite the Chinese military buildup in general and in the South China Sea in particular, together with its assertive claims to small islands also claimed by other Asian states, Chinese behavior should be best understood as motivated not by the grandiose goal of gaining “hegemony” over the region, but—with the clearly worrisome exception of its claim to sovereignty over Taiwan—its security concerns over the U.S. military buildup in the Pacific.