Bloomberg | Marc Champion�and Golnar Motevalli: French President Emmanuel Macron�s trip to Washington is just the public face of what�s been an intensive effort by European leaders to rescue the nuclear deal with Iran from U.S. President�Donald Trump.

Fully focused on the Trump threat, they may be missing another one emerging in Tehran. Macron�s invocation of a new, more comprehensive accord won�t count for much without some kind of signoff from Iran -- which is starting to lose faith in the existing version.

Until recently, the consensus in Iran was to stick with the 2015 nuclear deal even if Trump pulled out. On this view, President Hassan Rouhani would take the high road, enjoy Washington�s diplomatic isolation, and expand trade with Europe.

Now an explosive alternative view, once confined to a minority even among Iran�s conservatives, has become commonplace: If the U.S. walks away, the�Islamic Republic�should do the same.

It should restart full-scale uranium enrichment, and possibly even leave the Nuclear Non-Proliferation Treaty -- as threatened by Mohsen Rezaei, a former senior officer in the Islamic Revolutionary Guard Corps, at a press conference in Tehran Wednesday. That would be tantamount to declaring an intent to build nuclear weapons.

Losing Faith

Whether Iran would go that far, following in�North Korea�s footsteps, is in doubt. A degree of posturing is inevitable as Trump�s May 12 deadline for walking out of the deal approaches.

Still, there has clearly been a shift. Even supporters of the accord have become skeptical about Europe�s readiness to stand up to Trump and make the deal work in America�s absence, according to Ellie Geranmayeh, an Iran specialist at the European Council on Foreign Relations in Brussels.

�There is genuine discontent at how far Europe is willing, or even capable of going to deliver something concrete in case the U.S. withdraws,� said Geranmayeh, who argued for a tougher European stance toward Trump at a�European Parliament�hearing earlier this month.

Iranian officials are losing faith that proposals to protect European trade from U.S. penalties will materialize, she said. Those include mechanisms to trade oil in euros, set up an investment fund to circumvent the unwillingness of major banks to risk U.S. fines, and reinstate so-called �blocking regulations� to protect European companies from secondary U.S. sanctions.

�Makes No Sense�

And with low expectations that Iran will be rewarded for commitments it�s already made, there�s little interest in making new ones.

Macron�s still unelaborated plan involves new curbs on Iran�s ballistic missile program and its regional military footprint. The prospect appears to have intrigued Trump. In Tehran, it�s seen as appeasement of a U.S. president who Rouhani on Wednesday dismissed as a �tradesman� with no knowledge of international affairs.

�The Supreme Leader is no fool,� said Saeed Laylaz, an economist and former adviser to Iran�s reformist governments. �Why would he, even after seeing that Iran hasn�t received the full benefits of the nuclear deal, now agree to accede to what the U.S. wants? It makes no sense.�

That argument commands support across Iran�s political system, which has often been sharply split over nuclear diplomacy with the West, according to Laylaz. �I do not see any difference of opinion or divide between the government and the wider state system on this matter,� he said.

�Not Us�

It resonates among the public too. Support for the nuclear accord has been eroded by its failure to deliver the promised foreign investment and jobs.

For the deal to achieve peace, �the Americans need to commit to it,� said Morteza, 40, an unemployed Tehran resident, who declined to give his last name. He recently sold his car to pay rent, a not uncommon plight as the currency plummets.

�If the U.S. doesn�t stick by its obligations then it�ll go back to before and we will start enriching uranium,� Morteza said. �It�s Iran�s right to do so, because they�re the ones violating it, not us.�

The prospect of Russian support may be one reason why Iran�s leaders are more confident about confronting the U.S. than they were in 2015.

Laylaz cited a Russian veto used in defense of Iran at the United Nations in February, and collaboration between the countries in Syria, where Russia�s military intervention has dramatically expanded its regional role.

�Right now we are in a Cold War with the Americans,� he said. �And we are not alone.�

� With assistance by Birgit Jennen