On paper, Warren’s and Sanders’s outlook, despite what they say on the campaign trail, is remarkably consistent with those of the centrists. If you took the names off the foreign-policy articles written by any of the candidates, aside from a couple of flourishes, the differences would be difficult to detect. All of them want to see a foreign policy driven by values. They want the United States to play a leadership role in world affairs, they are committed to U.S. alliances, and they have placed the fight against corruption at the center of their campaigns. The progressives are as tough rhetorically on Russia and China as the centrists are, if not more so. And yes, progressives want to end the forever wars and pull back from the Middle East, but centrists would go along with much of that rhetoric too.

Most of the differences in progressive and centrist foreign policy appear to be attitudinal rather than substantive. Progressives explicitly call for new ideas and new thinking but, besides the implications for the Middle East, what this directive means is still unknown. A few progressive think-tank experts, generally affiliated with the new Quincy Institute for Responsible Statecraft, advocate for a massive reduction in U.S. military capabilities and a global retrenchment, but neither Sanders nor Warren has said anything of the sort and both are committed, at least in principle, to NATO and to maintaining America’s alliances in Asia.

Uri Friedman: The Sanders Doctrine

Progressives are likely to identify climate change as the nation’s top national-security priority. Centrists are more likely to say the issue is one of the top three. Does the ranking really matter? Both camps intend to work on the environment, and neither wants to make geopolitical concessions to China in exchange for its cooperation.

Progressives appear to be more skeptical of trade and global markets, but as Obama-administration officials Jennifer Harris and Jake Sullivan point out in a recent piece, centrists are also thinking hard about pivoting from a neoliberal foreign economic policy to an approach that sees a much greater role for the state in investment and industrial policy.

However, the progressive and centrist schools of thought would produce quite different policies in a few areas.

Progressives want to cut the defense budget by approximately 12 percent immediately. About a quarter of these savings can come from ending military interventions in Afghanistan, Iraq, and Syria. They hope to find the rest by taking on what they see as a corrupt military industrial complex. Progressives acknowledge that these cuts may result in less capability abroad, but they argue that the United States should seek military sufficiency rather than military primacy. Achieving substantial defense-budget savings is likely to be an early priority of a progressive administration, not least because the funds are required for an ambitious domestic program. If the wealth tax and other revenue-raising measures fail in Congress or are struck down by a conservative Supreme Court, those outcomes will increase pressure on the defense budget.