“When we talk about immigration,” Bernie Sanders began, “the secretary will remember that one of the great tragedies, human tragedies, of recent years is children came from Honduras.” Surely this was going to be it. The Democrats were holding their last scheduled presidential debate in Miami, on Univision, just one week after Berta Cáceres, the internationally renowned indigenous rights and environmental activist, was murdered in her native Honduras—the latest in a bloody onslaught of targeted killings unleashed by the 2009 military coup that Hillary Clinton, then at the helm of the State Department, had worked behind the scenes to legitimate. Six days out from the March 15 Florida primary, Sanders couldn’t have asked for a better opportunity to highlight one of the most questionable episodes in Clinton’s foreign policy record.

Instead, Sanders finished his thought with a vague denunciation of Clinton’s prior support for child deportation, a practice she has said sends a “positive message” to the thousands of families and unaccompanied minors fleeing poverty and conflict-levels of violence in their home countries. For this, too, Clinton deserves to be scrutinized. But in doing so, Sanders confined his attack to the usual tired parameters of immigration discourse, treating the issue as a battleground for domestic politics, rather than a crisis of foreign policy. Given the chance to elevate a pressing international issue—and score some political points in the process—Sanders played it safe.

Ignorance is one plausible explanation for this easy opening squandered. Sanders’s campaign doesn’t have much in the way of foreign policy advisers, and he certainly wouldn’t be the only leftist to have tuned out Central America after the dirty wars of the Reagan era subsided. But the larger pattern suggests Sanders has made a conscious choice to avoid forcing the issue on foreign policy. It’s one thing to tour the post-industrial heartland calling for a new New Deal, and quite another for an avowed socialist to start taking on the national security state. The country, Sanders seems to have decided, can only handle so many upheavals at once.  

Politically, a cautious approach may well have been the correct one. Principled stands on behalf of the developing world are not exactly the stuff of which successful campaigns for the presidency are made. And Sanders has gotten a good deal of mileage out of his opposition to the Iraq War. He’s able to project a lot about his beliefs without having to talk much or very specifically about them.

Now that a Sanders presidency is once again a distant longshot, however, his reticence to engage with global affairs represents a true failure of imagination. By ceding dominion over foreign policy to Clinton, Sanders is not only depriving the country of a perspective it desperately needs, but also undermining the rest of his platform. Earlier this month, I argued that Sanders has articulated the implicit basis for a robust, even radical, recalibration of U.S. power. As he forges ahead in a campaign whose function, increasingly, will be to expand the political horizon, it falls to him to flesh that vision out—if not for the good of the United States, or the millions of people around the world whose lives are subjected to the consequences of its policies, then at least for the sake of his revolution.

A quirk of the Sanders campaign is that the more remote its prospects become, the greater its clarity of purpose. Does Sanders really want to be president? It’s never been entirely clear. But in the aftermath of the March 15 contests, the answer is largely irrelevant. The electoral math, in a way, has resolved the essential ambiguity of Sanders’s candidacy for him.

To his credit, Sanders seemed to anticipate his present situation weeks before it had fully coalesced. On March 1, the night of the first Super Tuesday, he laid the groundwork for what has since emerged as the prevailing logic for his continued presence in the race. “Thirty-five states remain,” he told an audience of supporters in his home state of Vermont, “and we are going to take our fight for economic justice, for social justice, for environmental sanity, and for a world of peace to every one of those states.”

Sanders can take credit for having meaningfully and demonstrably dragged Clinton closer to each of the lofty goals he laid out that night—except the one toward which Clinton is most in need of dragging. A President Clinton would exert more control over foreign policy than any other aspect of her agenda. The intellectual authors of Washington’s bipartisan militaristic consensus have already latched onto her campaign. And there’s reason to believe the neocon cohort would, too, in the ever more likely event that Donald Trump—who this week revealed to The Washington Post that he would take “an unabashedly noninterventionist approach to world affairs”—emerges as his party’s nominee. Clinton and Trump’s dueling speeches at this week’s annual AIPAC conference foreshadow a general election in which the Democrat will be able to stake a stronger national defense claim than the Republican, a first since John F. Kennedy beat up on Richard Nixon over the imaginary Soviet “missile gap.”

Another incident in the Miami debate showed just how far the political needle has shifted, and how little Sanders has done to push back in the opposite direction. Sanders was asked to comment on an interview he gave in 1985, praising the Nicaraguan Sandinista government and likening the Reagan administration’s dogged—and illegal—support of contra death squads to the blundered, U.S. proxy invasion of Cuba in 1961. Sanders’s answer was tellingly convoluted, starting with an unorthodox survey of CIA skullduggery in Latin America and ending with a rather uninspired concession that, yes, Cuba is in fact an “authoritarian undemocratic country.” Clinton’s follow-up, by comparison, was as precise as it was dishonest:

I just want to add one thing to the question you were asking Senator Sanders. I think in that same interview, he praised what he called the revolution of values in Cuba and talked about how people were working for the common good, not for themselves.

I just couldn’t disagree more. You know, if the values are that you oppress people, you disappear people, you imprison people or even kill people for expressing their opinions, for expressing freedom of speech, that is not the kind of revolution of values that I ever want to see anywhere.

Remember, this exchange took place just minutes after Sanders practically tiptoed around Clinton’s involvement in the creation of a legitimate humanitarian disaster in Honduras. Then appreciate what it means for Sanders, in any context, to allow a Democrat with a documented affinity for despots to smear him over positions that were, at the time, widely held among mainstream liberals.

Sanders could do the country a tremendous long-term service by offering a positive alternative to the Democratic Party’s rightward ideological creep on affairs of state. In Miami, as in previous debates, Sanders brought up the 1973 U.S.-backed overthrow of Salvador Allende in Chile. He presented it as an inherent wrong, and it was. But Sanders has never bothered to explain that the Chilean people were subsequently offered up as the original lab rats for the neoliberal experiment he so readily blames for the decline of the American middle class. What should be a coherent, integrated part of Sanders’s broader message comes off as a sort of honor badge from his activist days, decorative and superfluous.

Pundits have been goading Sanders for months now to “get serious on foreign policy.” By this, they’re trying to say that Sanders is insufficiently enthusiastic about bombing Muslim countries, instigating a new Cold War with Russia, and other courses of action the “serious” people who know about these things deem appropriate. But if Sanders is indeed committed to extricating the United States from its “perpetual warfare” footing, as his campaign platform claims, then he really does have to change the way he conceptualizes these issues. Creating a meaningful political constituency behind non-interventionism means connecting the destructive impact of U.S. foreign policy to areas the American people more reliably care about, starting with their wallets. With his convincing fluency on trade, Sanders is uniquely well-suited to convey that kind of holistic worldview. And at this point, what reason does he have not to try?

Last month, Politico’s Michael Crowley explained to “befuddled” observers why Bernie Sanders made an “arcane reference” to the 1953 U.S.-backed overthrow of Iranian Prime Minister Mohammad Mosaddegh. Crowley’s big reveal was that Sanders had once called for abolishing the CIA—a “radical” idea shared by such notorious subversives as Harry Truman, the president who created the agency, and John F. Kennedy, who expressed a desire to shatter it “into a thousand pieces” following the Bay of Pigs fiasco. That was in 1974, before the Church Committee began uncovering the rat’s nest of corruption and criminal malfeasance the agency had become, before cocaine started entering the United States under covert agency protection, before black sites and torture and the obstruction of the Senate Torture Report, and before the use of a remote-controlled aircraft to summarily execute a U.S. citizen. Anyone who thought the CIA was worth disbanding then hasn’t been given much reason to change their mind since.

But at a town hall in Nevada in February, Sanders said he had seen the light. “That was 40 years ago,” he explained. Today, of course, “the CIA plays an important role.” It was the kind of answer you’re expected to give if you want to be president of the United States. But Sanders probably isn’t going to be president, and that frees him up to aspire to something greater—the kind of lasting change that, as Sanders himself will tell you, no president can hope to accomplish on his or her own, anyway.