Thanassis Cambanis, a fellow at The Century Foundation, is the author of “Once Upon a Revolution: An Egyptian Story.” He is a columnist for the Boston Globe and blogs at thanassiscambanis.com.

One of Donald Trump’s campaign applause lines held that it was time for the United States to quit serving as the world’s policeman and take care of business at home.

Isolationist chestnuts like this are standard campaign fare for a certain kind of conservative; just before he embarked on the biggest expansion of American military interventionism, George W. Bush, too, ran against the idea of “nation-building.”


Set aside for a minute the fact that even during years of unabated war following Sept. 11, 2001, America has done very little nation-building. Forget, also, that it’s questionable just how accurate the shorthand of “world policeman” is to describe America’s role in today’s international security architecture.

The essential fact is that the United States sits at the pinnacle of a world order that it played a central role in designing, and which benefits no other country so much as it does — you might have guessed — America itself.

America runs a world order that might have some collateral benefits for other countries, but is largely built around US interests: to enrich America and American business; to keep Americans safe while creating jobs and profits for America’s military-industrial complex; and to make sure that America retains, as long as possible, its position as the richest, dominant global superpower. Rather than global cop, it’s more accurate to call America the world’s majority shareholder, investing its resources in global stability less out of charity than self-interest.

What this means is that as Trump develops his foreign policy — a dealmaking approach whose ultimate outlines we can only guess at — he will eventually have to walk back his promise or confront its real costs. It's easy to paint America as the rich uncle whom the world takes advantage of. That caricature certainly resonates with Trump’s voting base. But if Trump really tries to deliver on his promise and walk away from the world, the biggest price is likely to be borne by America itself.

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The United States and its allies, in the wake of World War II, built a web of institutions that had an ideological goal: to reduce the risk of another murderous global conflagration. The United Nations would serve as a political-diplomatic talk shop that would reduce the chance of accidental superpower war and create avenues for managing the conflicts that did break out. The World Bank and the International Monetary Fund were designed to minimize the risk of another Great Depression. An acronym soup of other institutions sprang up along the same lines. When memories of fascism were fresh and Washington feared the allure of communism, it made some far-sighted, pragmatic moves. It funded the Marshall Plan for Europe, paying so the continent could recover economically and emerge to become a pivotal U.S. ally--and a profitable market for US companies. U.S. military occupiers in Japan and South Korea decreed progressive reforms and land redistributions in order to outflank communists.

In some cases, America really has underwritten most of the funding for international institutions, whether their purpose is to monitor ancient ruins (UNESCO) or inspect nuclear sites (IAEA). It hasn’t done so out of altruism. The investment has paid itself back many times over. These institutions have worked imperfectly, but they build goodwill and reduce risk. That’s good for the world in general, but it’s great for America.

It's true that America's role is expensive. In 2015, America spent more than the next seven nations combined on defense. Worried about this gap in the years after 9/11, some American officials and neoconservative ideologues complained that “Old Europe” should pay more for its defense. Like Trump, they argued that Europe has been able to reap an economic windfall because America shoulders so much of the NATO security umbrella.

At best, this analysis is a dangerous exaggeration; Europe could and probably should shoulder more of the cost, but the US investment in NATO is worthwhile for its own sake. At worst, by threatening NATO, the “free-rider” trope sets up America to shoot itself in the foot – shaking its security and breaking up a system with huge direct benefits to Americans.

Rather than a nation rooked by crafty foreigners, it makes more sense to see America at the center of a web of productive investments. Here’s how it works:

First, most of America’s defense spending functions as a massive, job creating subsidy for the U.S. defense industry. According to a Deloitte study, the aerospace and defense sector directly employed 1.2 million workers in 2014, and another 3.2 million indirectly. Obama's 2017 budget calls for $619 billion in defense spending, which is a direct giveback to the American economy, and only $50 billion in foreign aid – and even that often ends up in American pockets through grants that benefit American farmers, aid organizations, and other US interest groups. The U.S. military, and the Veterans Administration, are an almost socialist paradise of equality, job security and full health care when compared to life for Americans not on the payroll of the Defense Department and its generously (even absurdly) remunerated contractors. The defense budget, by playing on America’s obsession with security rather than social welfare, allows Washington to pump a massive stimulus into the economy every year without triggering another Tea Party.

Second, America’s steering role in numerous regions -- NATO, Latin America, and the Arabian peninsula -- gives it leverage to call the shots on matters of great important to American security and the bottom line. For all the friction with Saudi Arabia, for instance, the Gulf monarchy has propped up the American economy with massive Treasury bill purchases, and by adjusting oil production at America’s request to cushion the effect of policy priorities like the U.S. invasion of Iraq in 2003.

Third, and most importantly, if you listen the biggest critics of the new world order, what you'll hear is that it’s rigged – in America’s favor. America’s “global cop” role means that shipping lanes, free trade agreements, oil exploration deals, ad hoc military coalitions, and so on are maintained to the benefit of the U.S. government or U.S. corporations. The truth is that America puts its thumb on the scale to tilt the world’s not-entirely free markets to America’s benefit. Nobody would be more thrilled for America to pull back than its economic rivals, like China.

Perhaps that’s why analysts in the business of predicting world affairs don’t think Trump is going to abandon America’s “world policeman” portfolio once he looks at the bottom line.

“Trump wants to be seen as projecting strength around the world and intends to expand spending on U.S. defense,” wrote Eurasia group’s Ian Bremmer shortly after the election. He might be more abrasive, and he might pressure some of America’s bottom-tier allies. But if he wants to be a strongman, he’ll have to keep America’s stick.

Obama, too, apparently thinks Trump will like being the world’s policeman even more than he’ll like being Putin’s friend. "There is no weakening of resolve when it comes to America's commitment to maintaining a strong and robust NATO relationship and a recognition that those alliances aren't just good for Europe, they're good for the United States. And they're vital for the world," outgoing President Obama said on his valedictory trip to Europe, claiming confidence that Trump shared that view of global alliances.

Within Trumpworld, there’s no question a real rift exists on this question. Isolationist-nationalist America-firsters, like Steve Bannon, really do want to see America pull back, and downplay the costs in the interests of their ideological goals. Profit-driven internationalists like Rex Tillerson, however, are intimately acquainted with the benefits of keeping an American hand in global affairs.

Trump might like the sound of handing in America’s resignation as global cop. His voters might like it even more. But if pulling back makes America poorer and more vulnerable, the costs will land squarely on Trump.

When it comes time to choose between the two camps, Trump might find himself torn between an isolationist camp he connects with emotionally and an internationalist one that will — in the gross calculus of profits and power — be more of a winner. That’s a feeble rationale for a sound international order, but it might be the best one going in the age of Trump.