Rouhani is walking a political tightrope at home

When President Hassan Rouhani touched down on Iranian soil after a dazzling week at the United Nations, he returned to criticism as well as cheers and applause. A crowd of demonstrators held placards and chanted the spent slogan "Death to America!" The protesters included members of the Basij militia, a hard-line paramilitary organization under the control of the Islamic Revolutionary Guards Corps (IRGC) and Supreme Leader Ayatollah Ali Khamenei.

The theatrics of the demonstrators reflect a much deeper conflict that is already underway in Tehran, as different factions debate whether Rouhani should have accepted a phone call from President Barack Obama, and, more important, whether Iran should trust the United States to unlock the stalemate over Iran's nuclear program. Even though Khamenei has apparently given Rouhani the authority to expedite nuclear talks, other leaders in key institutions, such as the IRGC, began this past weekend to express their disapproval. There is increasing evidence that a broader opposition to Rouhani has begun to organize to derail any further progress from his diplomatic efforts.

In Iran's first public, high-level criticism of Rouhani's U.N. visit, Gen. Mohammad Ali Jafari, chief of the IRGC, said: "Just as he refused to meet Obama, he should also have refused to speak with him on the telephone and should have waited for concrete action by the United States." Jafari also said, in an interview with the Tasnim news agency, "If we see errors being made by officials, the revolutionary forces will issue the necessary warnings."

The operative word here is "revolutionary." Jafari, defying a warning Rouhani issued to the Guards in mid-September to stay out of politics, is drawing a distinction between Rouhani and the president's political faction anchored around former President Ali Akbar Hashemi Rafsanjani, and those who are seemingly more loyal to the values and ideology of the 1979 Islamic revolution. If, indeed, a line in the sand is being drawn, this is a remarkable development in Iranian politics whereby even the clerics of the system — such as Rouhani, one of Khamenei's advisers and confidants for decades — are too far to the left to silence the hard-liners.

Such statements should also serve as a warning to the U.S. and its European allies to move slowly so that Rouhani has time to build a broader base of support that could stand up to the Guards. Not only does the IRGC have vast economic interests that could be damaged if a nuclear deal is struck and sanctions are lifted on Iran, but the Guards' enormous political power would become less significant if Tehran and Washington reconciled. Its revolutionary ideology, which is based upon anti-Americanism, will have less social currency if Iranians suddenly reap economic rewards from warmer relations with the United States.

A thaw in relations with the U.S. is likely to include direct airline flights, scholarly exchanges, social interaction and deeper Western cultural influence — all of which are considered a threat to Iran's existence by its ultraconservatives. In reading Jafari's warnings and those of other hard-liners, I recalled the years I lived in Iran, from 1998 to 2001, when Mohammad Khatami was president and some within the IRGC tried to stage a coup to remove him from office. I was a foreign correspondent, and the plotters wanted to give me a videotape of a secret meeting in which they planned Khatami's demise. The coup was aborted in the end by IRGC leaders.

Like Rouhani, Khatami tried to end Iran's isolation from the United States and Europe, and favored social liberalization within Iranian society. Though Khatami survived his term in office, he ultimately failed to implement reforms primarily because he did not have the support of Khamenei and hard-line political factions. Even though Rouhani does have Khamenei's support for the policies he believes are necessary to end sanctions and his country's isolation, this endorsement has yet to be tested against the strong currents within Iran's entangled politics.  

The demonstrators shouting "Death to America" may not reflect widespread opinion in Iran. Still, such extremism has the potential to torpedo Rouhani's efforts. In the same way the White House did not admonish him for the missed chance of a handshake with Obama at a diplomatic lunch last week and instead favored a phone call to the Iranian president, the same caution should be applied as the nuclear talks move forward.

Threats of "all options are still on the table" — the cliche Obama used in his meeting on Monday with Israeli Prime Minister Benjamin Netanyahu to reference a possible military strike against Iran if a nuclear deal is not reached — should be removed from the White House's vocabulary. Such rhetoric only empowers Rouhani's foes and reaffirms their profound belief that Washington's ultimate goal is regime change in Iran. If there is any chance for reconciliation, the United States must not underestimate the challenge Rouhani faces at home.

Opinions expressed here do not necessarily reflect those of Al Jazeera America.