Among the most dispiriting aspects of Iranian policy since the 1979 revolution has been the seizure of foreign hostages.

From the 444-day ordeal of 52 Americans in the immediate aftermath of the revolution to the present-day captivity of three Iranian Americans and four other dual nationals, this policy has blackened Iran’s reputation and stymied its path to global re-integration.

In a world full of crises and violence, relatives and friends of those incarcerated in Tehran’s Evin prison have struggled to find a way to keep these cases in the news and to boost the ability of foreign governments to secure their release.

The US had its best leverage before implementation of a complex nuclear deal in January and succeeded in freeing five Americans, including journalist Jason Rezaian, in return for the release of seven Iranians jailed in the United States.

Iran did not release Iranian American businessman Siamak Namazi, however, and in February arrested his 80-year-old father, Baquer, also a dual national, who had been lured to Tehran on the promise of getting to see his imprisoned son.

Bijan Khajehpour, a relative by marriage of the Namazis who himself spent 3 ½ months in Evin in 2009 during a massive crackdown following fraud-tainted presidential elections, suggests offering to remove additional Iranian companies from a US Treasury Department blacklist, with the understanding that those companies and possibly additional ones would be sanctioned if Iran incarcerates more Iranian-Americans.

Khajehpour, a managing partner at Atieh International, a consulting firm that advises foreign companies on business in Iran, says there are entities in Iran that remain on a so-called specially designated (SDN) list that are not affiliated with the Iranian Revolutionary Guard Corps (IRGC) or other banned groups.

Khajehpour attributes the continued arrest of dual nationals to efforts by the intelligence branch of the IRGC to prevent Iran from fully benefiting from the sanctions relief afforded under the nuclear deal.

This shadowy body, with the evident permission of Iranian Supreme Leader Ayatollah Ali Khamenei, is seeking to undermine President Hassan Rouhani and Foreign Minister Javad Zarif in a complex struggle for power now and for influence later over succession to Khamenei, 77.

“Their message is: ‘You can’t ignore us, we are here and we have power,’ ” Khajehpour told a group of journalists during a visit to Washington. “The hardliners fear that the more moderate factions are gaining in influence and want to create leverage – both internally and externally,” he said.

The latest Iranian American victim is Robin Shahini of San Diego, an advocate of human rights on social media who had gone to Iran to see his ailing mother.

The other dual nationals in prison in Tehran are Nazanin Zaghari-Ratcliffe, an Iranian-British woman who was seized while visiting her parents with her toddler daughter; Nazak Afshar, a French-Iranian who had been previously detained in 2009 while working for the French Embassy in Tehran; and Homa Hoodfar, an academic and specialist on women’s issues from Canada. Also being held is Nizar Zakka, a Lebanese citizen who holds a US green card.

The husband of the Iranian-British hostage has mounted an aggressive campaign on social media to seek freedom for his wife, with frequent email updates to all those who sign a petition for her release.

The Namazis have been more inhibited in part out of concern for Siamak’s mother, Effie, who has remained in Tehran so that she can periodically visit her son and husband.

Khajehpour and friends of the family are hoping that a resolution can be found before President Barack Obama leaves office next January and that those holding Siamak and Baquer will realize that they are likely to face a tougher environment under Obama’s successor.

US officials have spent three decades contending with factions in Iran and have historically had great trouble trying to boost more pragmatic elements. Given the historic nature of the nuclear agreement and the bilateral channels it established, however, the Obama administration is in a position to make maximum efforts to secure the release of Iranian-American prisoners in a way that does not jeopardize these gains.

This analyst has previously advocated a number of steps to shore up the nuclear agreement including helping Iran increase the transparency of its financial system and authorizing multinational institutions to lend to Iran for environmental projects. It is also vital that Boeing be allowed to go through with a multibillion-dollar deal that will improve airline safety for ordinary Iranians and provide additional insurance that Iran will continue to implement its nuclear promises for the long term.

Continued engagement is the best way to defeat those in Iran who want to keep the country isolated from the West. In the meantime, international media should not forget these unfortunate dual nationals and the scores of other Iranians imprisoned for seeking a better future for their country.

Barbara Slavin is Acting Director of the Future of Iran Initiative at the Atlantic Council’s South Asia Center.