Volker served as U.S. permanent representative to NATO from 2008 to 2009 and later as special representative for Ukraine negotiations. He is now a senior fellow at the Center for European Policy Analysis.

Have European allies publicly criticized U.S. Iran policy before?

Yes. European leaders openly opposed Trump's 2018 withdrawal from the Iran nuclear deal and have consistently advocated for diplomatic engagement over military pressure.

What are the alternatives to public criticism?

Volker appears to favor private diplomatic channels, where European governments can express concerns directly to U.S. officials without creating public divisions that harden positions.

Ex-NATO Envoy Tells Europe: Keep Trump Iran Criticism Private

Q: Why does Volker think European criticism would backfire?

He argues that public dissent weakens the alliance's united front without changing U.S. policy, potentially emboldening adversaries who seek to exploit NATO divisions.

WASHINGTON —

A former U.S. ambassador to NATO is urging European allies to keep their concerns about President Donald Trump's military operations against Iran behind closed doors, warning that public criticism could backfire and damage transatlantic unity at a critical moment.

Kurt Volker, who served as the U.S. permanent representative to NATO from 2008 to 2009, made the comments on Politico's "EU Confidential" podcast Friday, according to The Hill. His advice comes as European governments navigate the delicate balance between maintaining alliance cohesion and expressing reservations about U.S. foreign policy decisions they may view as destabilizing.

"You might think that this is a huge folly and going to have terrible consequences, but you don't have to say it," Volker told the podcast. "By saying it, you make it worse."

The Transatlantic Dilemma

Volker's warning highlights a recurring tension in the NATO alliance: how European members should respond when the United States takes unilateral military action that affects shared security interests. The Trump administration's approach to Iran has included military strikes, maximum pressure sanctions, and threats of further escalation—moves that have often caught European allies off guard.

European nations, particularly France, Germany, and the United Kingdom, have historically favored diplomatic engagement with Tehran and worked to preserve the 2015 nuclear agreement that Trump withdrew from during his first term. Public disagreement over Iran policy has previously strained U.S.-European relations, with European leaders openly criticizing American decisions they viewed as undermining regional stability.

Volker's counsel suggests he believes such public dissent is counterproductive. By voicing criticism openly, he argues, European allies risk weakening the alliance's united front without changing U.S. policy—potentially emboldening adversaries who seek to exploit divisions within NATO.

The Case for Silence

The former ambassador's position reflects a school of thought that prioritizes alliance management over public accountability. Proponents of this approach argue that private diplomatic channels offer European governments a more effective avenue for influencing U.S. decision-making than public statements, which can harden positions and create domestic political pressures that make compromise more difficult.

This strategy assumes that quiet diplomacy carries weight in Washington—an assumption that critics say has been tested during the Trump administration, which has shown willingness to act unilaterally on issues from trade to defense spending to Middle East policy.

Volker's comments also raise questions about the role of public discourse in democratic alliances. If European publics oppose U.S. military actions that could draw their own countries into conflict, should their elected leaders remain silent to preserve diplomatic comity? The tension between democratic accountability and alliance solidarity has no easy resolution.

The Broader NATO Context

The advice comes at a time when NATO faces multiple challenges to its cohesion. Trump has repeatedly criticized European allies for insufficient defense spending, threatened to withdraw from the alliance, and pursued foreign policy initiatives—including direct engagement with Russia—that have alarmed European capitals.

European leaders have responded with a mix of accommodation and assertion, increasing defense budgets while also exploring greater strategic autonomy. France's President Emmanuel Macron has called for Europe to reduce its dependence on American security guarantees, a position that has gained traction as U.S. foreign policy becomes less predictable from a European perspective.

Volker's warning suggests he sees public European criticism of Trump's Iran policy as potentially accelerating this drift toward transatlantic separation. By keeping disagreements private, he appears to argue, European allies can maintain the alliance's operational effectiveness even when they disagree with specific U.S. decisions.

What Remains Uncertain

What we know: A former NATO ambassador has publicly advised European allies to avoid criticizing Trump's Iran military operations, arguing that public dissent damages alliance unity. What's unclear: Whether European governments will follow this advice, how the Trump administration would respond to either public or private European concerns, and whether quiet diplomacy can effectively influence U.S. policy decisions on Iran. The extent of current U.S. military operations against Iran and the specific European concerns Volker is addressing also remain unspecified in available reporting.