President Donald Trump has done what few thought possible: he helped broker a sweeping ceasefire between Israel and Hamas, negotiated the release of hostages, and achieved the first genuine breakthrough toward calm in nearly a year. For Israelis, the deal means quiet skies and the return of abducted families. For Palestinians, it offers desperately needed relief. For Americans, it represents a rare moment of when diplomacy actually worked.

And yet, the reaction from much of the American Left has been silence. The same political and moral voices that have spent months demanding a ceasefire in Gaza have fallen mute now that one has arrived. Even Barack Obama, who cautiously said we should all be “encouraged and relieved,” stopped short of acknowledging Trump’s role. Progressive leaders and influencers who once posted daily about “ending the killing” have said little. Media outlets that elevated every previous diplomatic setback have moved on.

It is a remarkable dissonance: the very outcome so many claimed to desire — peace, de-escalation, humanitarian access — has been achieved, but by the wrong hands. That contradiction tells us something profound about the state of American civic life. Our politics have become so saturated by affective polarization, so defined by visceral emotional hostility toward the other side, that many cannot even celebrate peace if it arrives through a political rival.

Affective polarization is more than disagreement. It is the phenomenon, now well-documented by scholars like Shanto Iyengar and Lilliana Mason, in which partisans grow to hate and distrust their opponents as people, not merely oppose their ideas. It is a moral emotion more than a rational stance: disgust, fear, contempt. The more one side is loathed, the more moral it feels to reject everything associated with it. This emotional sorting has turned politics into a theater of identity rather than a contest of policy.

That is why so many on the Left cannot bring themselves to give Trump credit for this deal. In a healthy political culture, a ceasefire and hostage release would be an occasion for shared relief, if not gratitude. But in our polarized one, positive feelings toward an opponent are experienced as betrayal. To say that Trump succeeded is not, in the mind of many progressives, to acknowledge a fact; it is to wound one’s tribe. The reaction becomes moralized: silence as purity, acknowledgment as contamination.

Political sorting has made this response all but inevitable. Over the past several decades, many Americans have come to live, worship, and socialize with those who think like themselves. Partisanship now defines moral boundaries and social identity. To be “on the Left” no longer simply means favoring redistributive policies or progressive reforms, it means belonging to a moral community defined in opposition to Trump and the movement that supports him.

When identity is at stake, the ordinary norms of evaluation break down. The achievement of peace becomes inseparable from the personality associated with it. The act cannot be good if the actor is, in the tribe’s imagination, evil. As affective polarization deepens, moral reasoning collapses into reflex. Emotion crowds out judgment.

This isn’t unique to the Left, of course. Conservatives behaved similarly under Obama, dismissing or minimizing his role in successes such as the raid on Osama bin Laden or sanctions on Iran. But today’s reaction carries a different weight. The moral intensity that animates the modern progressive movement — its conviction that it alone occupies the side of justice — makes acknowledgment of an opponent’s virtue especially threatening.

Affective polarization doesn’t just distort how people feel about politics; it reshapes how they feel about truth. Once emotions determine perception, facts that contradict the emotional order must be ignored or reframed. This is why even a genuine diplomatic success can be spun as suspect: perhaps the deal was coerced, perhaps it was opportunistic, perhaps it will fail. These rationalizations serve an emotional function, they preserve the purity of contempt.

Former President Obama’s muted response captures the dilemma perfectly. He offered relief without recognition, validation without credit. The avoidance is deliberate. He knows that open praise of Trump would fracture the progressive coalition that still reveres him. Acknowledging the achievement would invite accusations of appeasement or betrayal. In an era of affective polarization, even measured generosity risks being reinterpreted as treason to the cause.

But this silence comes at a moral cost. When leaders cannot acknowledge good done by their adversaries, they model a politics of negation. They teach citizens that truth is partisan and that virtue is contingent on affiliation. The habit of withholding praise corrodes the civic trust that democratic life requires. It signals that what matters most is not reality but narrative: the preservation of emotional coherence over empirical fact.

That logic now governs much of American political life. The reaction to Trump’s Middle East deal is simply the latest and starkest case.

This is how affective polarization hollows out moral courage. It makes sincerity dangerous and honesty costly. It turns politics into a form of emotional hygiene, where purity must be maintained at all costs. The moment we fear that recognition of another’s good deed might “taint” us, civic reasoning has already given way to tribalism.

The tragedy is that this pattern is self-reinforcing. Each refusal to acknowledge the other side’s success deepens distrust and confirms the caricature.

The result is a democracy that can no longer experience joy together. A moment of peace in the Middle East becomes not a unifying event, but another test of loyalty. Even moral goods, saving lives, freeing captives, are recoded through partisan emotion.

There was a time when American leaders resisted that temptation. When Richard Nixon opened up to China, Democrats recognized its strategic value. When Jimmy Carter mediated peace between Israel and Egypt, Republicans offered credit. When Ronald Reagan forged arms agreements with Gorbachev, Democrats applauded the breakthrough. These gestures were not signs of weakness, but of civic strength. They reflected a shared moral confidence that truth and goodness could exist outside partisan lines.

We have lost that confidence. Affective polarization has made cross-party acknowledgment feel morally dangerous. It has replaced civic humility with moral narcissism.

The solution begins with a small but radical act: honesty. A willingness to recognize good wherever it appears, and to praise virtue even when it originates in the hands of a rival. That act does not diminish one’s convictions; it dignifies them. It affirms that truth exists independently of our tribes, that moral worth is not determined by partisanship, and that peace — real, tangible, human peace — is a universal good.

The ceasefire and hostage release will face challenges, as all fragile peace deals do. But for now, lives have been spared, families reunited, and the possibility of stability renewed. That is cause for gratitude, not partisan discomfort.

Peace, like truth, does not belong to one party or president. It belongs to all who value life over politics. To say so should not require courage. But in today’s polarized America, it does.

And that, perhaps, is the clearest measure of how much work remains to be done.

Samuel J. Abrams is a professor of politics at Sarah Lawrence College and a senior fellow at the American Enterprise Institute.