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In 2016, Donald Trump took on and defeated the Republican foreign-policy establishment. Some progressives wonder if they may be able to accomplish the same feat in the Democratic Party in 2020. They are looking for a nominee who rejects the post–Cold War bipartisan consensus, which they believe makes the United States too quick to get into wars and too committed to American primacy, in favor of a strategy of restraint.

The newly formed Quincy Institute for Responsible Statecraft—founded with large grants from the Charles Koch Foundation and George Soros’s Open Society Foundations—is the latest addition to this effort. Quincy seeks to bring together progressives with anti-intervention conservatives to “restore the pursuit of peace to the nation’s foreign-policy agenda,” as its co-founder Andrew Bacevich put it. It’s not just Quincy. A number of scholars and experts have written thoughtful pieces trying to flesh out a progressive alternative.

If the progressives succeed, we could be on the cusp of a revolution in U.S. foreign policy along the lines of the rise of internationalism in the 1940s or neoconservatism in the 1980s. However, the revolutionaries have their work cut out for them. Thus far, the progressive presidential candidates are closer to President Barack Obama’s worldview than their rhetoric lets on.

The progressive candidates have signaled their desire to pursue a policy in which the United States reduces its military commitments overseas—what is usually called a “foreign policy of restraint.” The interesting question, though, is whether that is possible at an acceptable cost. Outside of the Middle East, the answer is almost certainly no. If they were to go further toward adopting a strategy of restraint whereby the United States does much less militarily around the world, they would have to make major sacrifices on alliances, nuclear proliferation, and spheres of influence that no Democratic commander in chief seems likely to want to make.

Two candidates for president—Bernie Sanders and Elizabeth Warren—have embraced the progressive-foreign-policy label. Reading their speeches and articles, two major themes stand out.

The first is that Sanders’s and Warren’s specific ideas to change U.S. foreign policy are focused on the Middle East. They oppose military intervention in Syria and Iraq. They support the Iran nuclear deal. They want to get tough with Saudi Arabia, going beyond simply ending U.S. support for the war in Yemen. Both favor an end to the war in Afghanistan, and both have questioned the extent of ongoing operations against terrorist networks. Sanders and Warren do differ over Israel—Sanders is very critical of Israel and has questioned U.S. aid, whereas Warren is generally seen as supportive of the alliance.

However, when you drill down, the two presidential candidates are difficult to pin down on whether they oppose military intervention on principle or, if not, under what conditions they might support it.

Sanders opposed the Vietnam War, the Gulf War, and the Iraq War of 2003, as well as numerous U.S. interventions in Latin America and the Middle East. However, he also voted for the Iraq Liberation Act of 1998 and later called Saddam Hussein “a brutal dictator who should be overthrown.” He opposed Operation Desert Fox, a bombing campaign in Iraq in 1998, primarily because it did not have congressional or United Nations approval, but also because he did not think it would bring about regime change. He voted for the 1999 Kosovo War and subsequently supported the NATO bombing campaign, even as he argued that President Bill Clinton’s failure to secure congressional support meant it was unconstitutional. He voted for the 2001 Authorization for Use of Military Force and did not oppose the 2011 intervention in Libya in its initial stages, when the sacking of Benghazi by Muammar Qaddafi’s forces seemed imminent.

Unlike Sanders, Warren never had to vote or comment on these interventions. She has been careful not to shed any light on her views on them since becoming a U.S. senator. However, Warren does have a track record from when she entered politics in 2012. In Warren’s first-ever speech on foreign policy, at Georgetown University in 2014, she implicitly criticized Obama for not being sufficiently sensitive to civilian casualties in his drone strikes. In 2014, she said that the defeat of ISIS should be the Obama administration’s top priority, but that the United States should avoid getting dragged into a war. She supported Obama’s air strikes in Iraq in 2014, while opposing his plan to train and equip Syrian opposition forces.

A Warren adviser, who spoke under the condition of anonymity to engage in a broad-ranging discussion on the senator’s worldview, told me that Warren sees force as a last resort, and that when it is employed, she believes there should be an exit strategy, it should be limited, and it should be multilateral, preferably through the United Nations. It’s a position that sounds almost identical to Obama’s.

The 44th president was also deeply skeptical of military interventions, but found himself drawn in. For instance, by 2014, Obama had pulled American troops out of Iraq and was holding fast against involvement in Syria. But the rise of ISIS, the beheading of hostages, and the fall of Mosul created a groundswell of public pressure to deal directly with the threat. It was a reminder that even a president skeptical of intervention is one terrorist attack away from getting involved. That dynamic will not change in 2021. A progressive president is unlikely to argue that the United States should be indifferent to an ISIS-style group in the Middle East that conquers territory or attacks Americans. Sanders’s track record suggests that he is more pragmatic than he lets on.

There is little doubt that Sanders and Warren are sincere in their desire to prioritize diplomacy over the use of force, but here, too, they have a dilemma: When it comes to preventing a rogue state from acquiring nuclear weapons, a credible threat to use force often creates the leverage necessary to get the other side to the table. In her book, Wendy Sherman writes about how the Obama administration deliberately deployed a bomb that could penetrate Iran’s underground enrichment facility, “backing up our diplomacy with the credible use of force.” Would Sanders and Warren do the same thing? If not, what’s their theory of building leverage? Matt Duss, who serves as Sanders’s foreign-policy adviser, told me that Sanders is “against large-scale military interventions or the threat of them, and would rely more on economic sanctions to create leverage for negotiations like those for the Iran nuclear deal.”

The second theme is that both of them draw a dramatic divide between democratic and authoritarian states. In a major address at the Johns Hopkins University School of Advanced International Studies, Sanders said:

There is currently a struggle of enormous consequence taking place in the United States and throughout the world. In it, we see two competing visions. On one hand, we see a growing worldwide movement toward authoritarianism, oligarchy, and kleptocracy. On the other side, we see a movement toward strengthening democracy, egalitarianism, and economic, social, racial, and environmental justice. This struggle has consequences for the entire future of the planet—economically, socially, and environmentally.

Sanders went on to identify the authoritarian movement as including Brazil’s Jair Bolsonaro, Russia’s Vladimir Putin, Israel’s Benjamin Netanyahu, Saudi Arabia’s Mohammed Bin Salman, and President Trump, whom Sanders sees as on the wrong side of the struggle between autocrats and democrats.

In her Foreign Affairs essay, Warren struck a similar note:

Authoritarian governments are gaining power, and right-wing demagogues are gaining strength. Movements toward openness and pluralism have stalled. Inequality is growing, transforming rule by the people into rule by wealthy elites. And here in the United States, many Americans seem to accept—even embrace—the politics of division and resentment.

Warren has focused more on China than Sanders, although Sanders intends to address China more in the coming months.

For both candidates, the democracy-versus-autocratic-oligarchs framing is a way to kill several birds with one stone. It allows them to talk about the global economy as a rigged system and to fight inequality. It is a way of getting tough with Russia and China. It allows them to stand up for democracy and human rights. Most important of all, it allows them to paint Trump as part of a global problem.

However, democracy versus autocracy is not a radical departure from traditional Democratic foreign policy. Both Sanders and Warren essentially accept the diagnosis of more hawkish Democrats that the United States is locked in a geopolitical struggle with authoritarian regimes, but they depart significantly on the prescription—they would both slash the defense budget and switch the topic away from geopolitical rivalries and toward inequality, economic policy, and democracy. This sets up a fundamental contradiction: Sanders and Warren will be forced to choose between waging the struggle against autocrats and cutting the defense budget and deemphasizing military power.

Writing in War on the Rocks, a longtime adviser to Warren, Ganesh Sitaraman, argues that there is no such contradiction. “When progressives use hawkish language,” he says, “they are doing so with respect to economic challenges, not with an eye toward military buildups and war.” The Warren adviser I spoke with said that the senator is generally happy with America’s traditional strategic role in Europe through NATO, but that she would be taking a close look at the U.S. military footprint in the Asia Pacific. Economic competition would be Warren’s primary focus with regard to China. They went on to say, “It’s important to defend our systems and values; it is possible to engage in a robust defense of our system without ending up in a military conflict.”

Many Democrats believe that diplomatic and economic tools are more benign than and preferable to the deployment of troops and deterrence, so it is no surprise to see progressives embrace their use. But the reason Russia and China have a problem with the Western order has as much to do with soft power as with hard power. It is the prospect of color revolutions, fed by a free press, open information networks, anti-corruption measures, and the wide appeal of democratic ideas that scares Moscow and Beijing the most, not tanks in eastern Europe or aircraft carriers in the Pacific. Take the example of Hong Kong. China does not worry about Western military intervention. What it views as a threat are statements of support for the protesters—exactly of the kind that both Sanders and Warren have issued. Even when it comes to hard power, China worries less about military interventions and more about the long-term balance of power.

There’s nothing wrong with using these measures to counter Russian and Chinese influence. (I’ve written regularly in support of them.) However, it’s important we acknowledge that this is a competitive and tough policy that incurs risk. Sanders and Warren give the impression that they believe this choice is inherently more benign than the blob’s approach and they can opt out of military competition. In truth, escalating political warfare while pulling back militarily could create an incentive for America’s rivals to test the United States. Deterring geopolitical aggression—whether in the South China Sea or Ukraine—will become a precondition for managing and limiting tensions.

If Sanders or Warren is elected, they will find themselves confronted with these questions immediately. Indeed, some progressives and commentators worry about precisely that. For instance, Daniel Bessner of the University of Washington and Udi Greenberg of Dartmouth College recently wrote in The Nation, “For all their ingenuity, both candidates sometimes insist that this moment is defined by a battle between good and evil. In doing so, they frame geopolitics in simplistic terms that undermine the left’s long-term goals.” Bessner has argued for a more radical foreign-policy agenda for Democrats akin to that espoused by the Labour Party leader, Jeremy Corbyn.

Others have argued that the Democrats are just offering up a new version of American hegemony. Janan Ganesh of the Financial Times lambasted Democrats for failing to question the assumptions of leadership, and argued that on foreign policy, they were “stranded in time.”

I put this to Duss. He felt the critics were underplaying the extent of change on military intervention in the Middle East, as evidenced by Sanders’s work to stop the war in Yemen. He told me that when it comes to Europe and Asia, “there are no prebaked plans, but there is a willingness to ask fundamental questions, listen to new ideas, and to develop a new consensus.” “Very little is sacrosanct,” he said. He expressed the hope that organizations such as the Quincy Institute would inject the Washington debate with a new vigor. Duss did make the point that Sanders is not an old-style leftist. “Some leaders are hostile to the very idea of American power, but Senator Sanders is not one of those,” he said. “The question is when and how that power is deployed. American diplomacy, humanitarian and development aid are formidable tools, and he will work closely with allies to use those tools to create a more peaceful world.”

To understand why Sanders, Warren, and other Democrats are unlikely to embrace a foreign policy of restraint, it is useful to look at restraint’s intellectual origins. No one has thought more deeply about how to implement a strategy of restraint than academic realists—the school of thought within foreign policy that defines national interests narrowly, sees the world in terms of power politics, and believes that the United States is massively overextended in the world. If you read the realists closely, it’s clear that they believe restraint is only possible if the United States takes radical action—actions at which almost all progressives would balk.

It’s hard to do less while maintaining America’s alliances in Europe and Asia. The academic realists who developed the theories of restraint understood this. For instance, in his 2015 book, Restraint, the MIT professor Barry Posen argues that the United States should withdraw from NATO. Progressives understand how toxic this is, which is why they have rejected it. But if presidents simply confine themselves to tough talk about how allies need to do more, they will be following the pattern set by Obama.

Realists recognize that retrenchment means accepting that America’s rivals will acquire and expand their own spheres of influence. They don’t see it as a problem up until the point that rivals appear poised to dominate their entire region. Some progressives have come around to this idea. Writing in these pages, Peter Beinart argued that Sanders and other Democrats must accept that China is displacing the United States from part of Asia.

Spheres of influence are incompatible with Sanders’s and Warren’s description of a struggle between authoritarianism and democracy, but even laying that aside, the approach is fraught with risk. The lines of such spheres are unclear and would be subject to constant revision, often through the use or threat of use of force. If even China and Russia are entitled to their spheres, why not Japan, Britain, and Germany? And would the United States, particularly under a progressive president, seriously sit down with a Chinese or Russian leader and divide up the world over the objections of the smaller countries that would be served up?

Indeed, China’s rise has been so rapid that many realists are rethinking their previous support for restraint. Jennifer Lind, a professor at Dartmouth, told me:

The restraint school that emerged in the late 1990s counseled husbanding resources for the “main event” of a regional peer competitor. Sadly, no one listened to them; America’s power and position are weaker today as a result. But today we’re seeing an increasingly powerful and assertive China: grabbing resources, ignoring international law, militarizing the South China Sea. Its neighbors can’t or won’t balance. The question for the restraint school is: At what point does China become the main event—and how should U.S. policy change when it does?

For their part, progressives are also much more comfortable with ending the forever wars accommodating China’s rise. In January, a few months before he helped set up the Quincy Institute, Soros gave an impassioned speech at Davos warning of “the mortal danger facing open societies from the instruments of control that machine learning and artificial intelligence can put in the hands of repressive regimes.” Soros called Xi Jinping “the most dangerous opponent of those who believe in the concept of open society.”

True restraint—whereby the United States significantly reduces its military commitments overseas—will be all but impossible for a Democratic president to achieve in a deliberate and orderly fashion. It would involve too many compromises of core principles. Progressive presidents will not want to pursue the destruction of the alliance system, acquiesce in nuclear proliferation, or embrace the imperialist notion of spheres of influence. They will be unable and unwilling to promise credibly never to intervene militarily.

It is possible that Sanders and Warren find themselves stuck between the mainstream national-security worldview they have articulated and their aspirations to opt out of geopolitical competition and military interventions. This could hobble the early years of their administration. Alternatively, they could embrace a practical and modest progressive approach. This would seek to pull back from the Middle East, keep the basic structure of America’s role in Europe and Asia intact while modernizing the military, sharpen the ideological divide with authoritarian states, and endeavor to change the world on specific issues, much as Obama did by opening up relations with Cuba, prioritizing climate change, and playing a constructive role in international institutions. In this, much of the blob would agree. If Warren or Sanders emerges as the nominee, there will undoubtedly be tensions and disagreements with the Democratic foreign-policy establishment, but this type of practical progressivism may form the basis for a rapprochement and an avoidance of the kind of schism Trump brought to Republican foreign policy.

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