Alarmed by Russian efforts to influence the 2016 U.S. presidential elections, U.S. media, strategists, and intelligence agencies await the upcoming midterm elections in November with consternation, warning of the danger of renewed meddling from Moscow. Yet new reports suggest that the Kremlin may have company in its efforts to shape the U.S. domestic information landscape: Iran.

In the past few days, Facebook and Twitter were among several platforms that announced the deletion of hundreds of suspicious social media accounts, which the companies said were linked to a systematic Iranian disinformation campaign abroad. According to FireEye, the cybersecurity firm that first raised the alarm, the groups associated with the campaign often presented themselves as independent news outlets but were in fact linked to Iranian state media. Their content was designed to push issues and narratives in line with Iranian foreign policy, promoting “anti-Saudi, anti-Israeli, and pro-Palestinian themes, as well as support for specific U.S. policies favorable to Iran, such as the U.S.-Iran nuclear deal.”

The revelations echo recent comments by National Security Adviser John Bolton, who called Iranian meddling a “national security concern.” But they should not come as a surprise to Washington: although Iranian disinformation efforts abroad have been fairly limited and there is no evidence that the recently deleted accounts were specifically designed to affect the outcome of the November midterms, Tehran is no stranger to information warfare. Like few other authoritarian regimes, the Islamic Republic has long understood that information is hard political currency.

In fact, the Islamic Republic’s disinformation tactics are as old as the regime itself. In the 1970s, Iranian revolutionaries fighting to topple the U.S.-backed monarch Mohammad Reza Pahlavi—known as the Shah—lacked today’s online technology but worked hard to use all available channels to amplify the voice of their leader, Ayatollah Ruhollah Khomeini. An exiled dissident cleric, Khomeini asserted himself as captain of the revolution and became the new theocratic regime’s first supreme leader after the Shah’s ouster in 1979. Khomeini’s close advisers, many of them Western-educated, helped him curate a message that would reach and appeal to several audiences at once: Iranians at home and abroad, the Middle East and the broader Muslim world, and the West. To Western audiences, Khomeini’s advisers presented a sympathetic freedom fighter striving to bring prosperity and freedom to his country. This often entailed omitting or modifying the cleric’s actual words to make his overall message more appealing to a Western audience. The strategy worked, in part because Western journalists covering the revolution and Khomeini’s rise often relied on the information and translations fed to them by his men, broadcasting their message to the world on radio, TV, and in newspapers.

At home, Khomeini’s followers set the stage for his rise with a subversive political campaign mixing propaganda with disinformation. They distributed pamphlets and cassette tapes featuring his speeches. The tapes were cheap, duplicable, and easy to conceal from the shah’s intelligence agency, the SAVAK. Thus, Khomeini’s voice and message gained influence on the streets of Iran even as he remained in exile in Paris. Ironically, the would-be revolutionaries were at times helped in their efforts by theshah himself, who initially failed to understand their ambitions and even amplified some Islamist voices in an attempt to counter what he initially considered the greater threat to his reign—communism.

The revolutionaries also understood the utility of fake news. They exaggerated the numbers of casualties during anti-regime protests and falsely blamed the shah for incidents like the 1978 Cinema Rex fire, which led to the death of at least 377 people in Abadan. The revolutionaries even went as far as suggesting that a 1978 earthquake in the city of Tabas wasn’t a simple seismic event but the result of Western countries dumping nuclear waste in a nearby desert or of U.S. underground nuclear tests. The Islamic Republic’s own official documents and statements would later contradict the revolutionaries’ narrative on several of these events.

Following the fall of the shah, the new regime institutionalized this revolutionary propaganda machine. A new state-run media apparatus helped control the narrative at home and disseminated favorable content abroad. In the decades that followed, virtually all of the regime’s main institutions began to build their own media outlets, many of them broadcasting in several languages. Today, English-language content serves to promote the regime’s narrative on various issues in the West, while programming in Arabic is designed to galvanize sympathetic Arab populations in the region.

While the anti-Saudi and anti-Israeli views promoted by Iranian social media accounts are hawkish positions in Iranian domestic politics, they tend to be associated with left-wing views in the United States.

Several organizations have emerged as information brokers. There is the Ministry of Intelligence and Security, which replaced the SAVAK after the revolution and has played a key role in framing and implementing the regime’s messaging campaigns. The paramilitary Islamic Revolutionary Guards Corps has its own intelligence unit and operates or indirectly controls several media outlets, including Fars News and the newer, more hard-line Tasnim News Agency. The Guards use these outlets and social media to criticize policies they deem contrary to the revolution, undermine domestic opposition, and publicize their activities abroad, for example by spreading imagery of Iranian military commanders in Iraq and Syria. Meanwhile, state-run media, such as the English-language channel Press TV, allow Tehran to appeal to sympathetic viewers in the West. Press TV and other state-run outlets often feature European or U.S. commentators voicing support for Tehran’s narratives and policies.

Although the regime has banned many social media platforms, including Facebook and Twitter, key officials and organizations within Iran use them to disseminate content in various languages to support Iranian policy agendas at home and abroad. They are supported in their efforts by a network of accounts directly or indirectly linked to the regime, which operate on a range of platforms, including Facebook, Twitter, and Instagram, as well as messaging apps such as Telegram and WhatsApp.

Interestingly, while the anti-Saudi and anti-Israeli views promoted by these accounts are hawkish positions in Iranian domestic politics, they tend to be associated with left-wing views in the United States, making Iranian efforts to shape the U.S. information landscape different from those undertaken by the Russian campaign in 2016, which often, though not exclusively, targeted more right-leaning voters.

The exact impact of the newly shut down accounts remains unclear, and Iran’s capabilities are much more limited than Russia’s, as it possesses neither the budget nor the technology and knowhow of Russian intelligence. But with U.S. sanctions designed to cut down Iranian oil exports to zero by November looming large, Tehran may not sit on its hands. As Americans prepare to return to the voting booths this fall, Washington would be well advised to look into Iran’s disinformation capabilities and intentions before it’s too late.