The Islamic Republic has taken a somewhat harsher tone in its reaction to the announcement that Bahrain will normalize relations with Israel than it did to the U.S.-brokered agreement between the United Arab Emirates and Israel, as expressed by the Islamic Revolutionary Guard Corps’ and the Bahraini Shia opposition based in Iran. What accounts for the nuances in the Islamic Republic’s reaction, and what is the likelihood of Tehran acting upon threats that it has made against Bahrain?

As the UAE and Israel began the process of normalizing relations, Islamic Republic officials and institutions communicated a relatively uniform message: The Foreign Ministry warned against “any intervention of the Zionist regime in regional equations” for which Iran would “hold the Emirati government and its allies responsible.” President Hassan Rouhani threatened to deal with the UAE “in a different manner” if it opens “the path to Israel’s presence in the region.” An IRGC statement reiterated the threats but also predicted “popular uprisings” against the Emirati rulers. Supreme Leader Ayatollah Ali Khamenei, who was the last major figure to comment on the issue, condemned “the treachery of the government of the United Arab Emirates,” but expressed hope that the UAE “awakens and makes up for what it has done.”

While the Islamic Republic’s reactions to Bahrain’s agreement with Israel hit similar points, in general, Tehran appears to have chosen a harsher line. Khamenei has yet to weigh in on the issue. But the Foreign Ministry strongly condemned the move, which it claimed sacrifices “the cause of Palestine” and, in line with its earlier warning to the UAE, stated that the Bahraini government “will be held responsible” should Israel “create insecurity in the Persian Gulf region.” Commenting on the issue on September 16, Rouhani warned: “The Emirates and Bahrain are trying to provide Israel with a base in the region and must accept responsibility for it.” It was unclear if the reference to “base” refers to military bases or is meant metaphorically. Apart from reiterating the warnings from the Foreign Ministry and Rouhani, the IRGC’s statement also launched a personal attack against the Bahraini monarch: “The executioner ruler of Bahrain should await the harsh revenge of the holy warriors of liberation of Quds [Jerusalem] and the honorable Muslim nation of this country [Bahrain].” The IRGC’s statement was topped by an interview in Shia News with Abd al-Saheb Yadegari of Allameh Tabatabai University, who expressed hope that Bahrain “finally will return to the fatherland,” a reference to Iran’s historic claim to Bahrain until March 1970. A similar statement made by a Kayhan newspaper editor on May 17, 2012 unleashed a crisis between Iran and Bahrain.

Unlike the Islamic Republic’s response to the UAE’s move, the IRGC’s warnings to the Bahraini government were followed by a stream of public statements from Bahraini Shia leaders and activists in exile, who expressed their opposition in Islamic Republic Persian- and Arabic-language outlets. Isa Qassim, the spiritual leader of Bahrain’s leading Shia political society, al-Wefaq, which was dissolved by the government in 2016, issued a statement condemning the normalization of relations and warning of the “growing gap between the rulers and the people” in Bahrain. Abdullah al-Daqaq, Qassim’s representative in Iran, condemned the normalization of relations as “treason” and “religiously prohibited” in line with “eating pork or drinking wine.” Abdullah al-Saleh of the Islamic Action Society also pointed at popular resistance to the Bahraini government’s initiative. So did Abdul Ghani al-Khanjar, the spokesman for the Haq Movement for Liberty and Democracy. Eyman al-Rabiee, a political activist in Qom, warned “The Bahrainis will not let the Khalifa dynasty’s deed remain unanswered.” The Bahraini opposition’s criticism of normalization of relations appears to have resonated with the Bahraini public, and “Bahrainis against normalization” was trending high on Twitter among Bahrainis, according to the Palestinian ambassador to the United Kingdom.

The Islamic Republic’s harsher reaction to Bahrain’s announcement that it would normalize relations with Israel is in part due to the greater opportunities available: Shia-majority, but Sunni-ruled Bahrain has experienced multiple political crises since 2011, and politically marginalized and radicalized Bahraini Shia leaders flock to the Islamic Republic to gather support. The Islamic Republic, in turn, has consistently attempted to manipulate the Shia struggle to its own political advantage, and the normalization of relations with Israel provides another grievance Tehran can use to mobilize Bahrain’s Shias against their rulers.

It is unclear what the IRGC means by its threats of “harsh revenge,” and there are limits to what the Islamic Republic can achieve in Bahrain: Since 2011, the Islamic Republic has worked to further undermine relations between the state and society in Bahrain, but the Al Khalifa ruling family remains firmly in power while the opposition is increasingly marginalized. Still worse, from Tehran’s perspective, such threats and senseless talk of Iranian suzerainty over Bahrain drive Manama ever deeper into the embrace of the Islamic Republic’s adversaries, including Saudi Arabia and Israel.