In fact, they stood on opposite sides of one of the world’s fiercest geopolitical divides. Yet in a secret effort at detente, two of the most formidable organizations in the Middle East held a previously undisclosed summit at a Turkish hotel to seek common ground at a time of sectarian war. The 2014 summit brought together the foreign military arm of Iran’s Islamic Revolutionary Guard Corps, known as the Quds Force, and the Muslim Brotherhood, a sprawling Islamist political movement with significant influence throughout the region. The Quds Force represents the world’s most powerful Shia-dominated nation, while the Muslim Brotherhood is a stateless but influential political and religious force in the Sunni Muslim world. The Trump administration designated the Revolutionary Guards a foreign terrorist organization in April, and the White House has reportedly been lobbying to add the Muslim Brotherhood to the list as well. The disclosure that two such polarizing organizations on either side of the Sunni-Shia divide held a summit is included in a leaked archive of secret Iranian intelligence reportsobtained by The Intercept. There were public meetings and contacts between Iranian and Egyptian officials while Muslim Brotherhood-backed Mohamed Morsi was president of Egypt from 2012 to 2013. But Morsi was forced from power in a coup supported by the Egyptian Army in July 2013 and later arrested. The regime of Abdel Fattah el-Sisi launched a crackdown on the Muslim Brotherhood, and many of its leaders have since been imprisoned in Egypt or are living in exile. An Iranian intelligence cable about the 2014 meeting provides an intriguing glimpse at a secret effort by the Muslim Brotherhood and Iranian officials to maintain contact — and determine whether they could still work together — after Morsi was removed from power. The cable about the summit, from the Iranian Ministry of Intelligence and Security, or MOIS, reveals the fraught political dynamics that separate powerful Sunni and Shia organizations like the Muslim Brotherhood and the Quds Force. Above all, the cable and the story of the summit expose the maddening complexities of the political landscape in the Middle East and show how difficult it is for outsiders, including U.S. officials, to understand what’s really going on in the region. On the surface, the Quds Force and the Muslim Brotherhood would appear to be archenemies. The Quds Force has used its covert power to help Iran expand its influence throughout the Middle East, backing Shia militias that have committed atrocities against Sunnis in Iraq, while siding with the brutal regime of Bashar al-Assad in the Syrian civil war. The Muslim Brotherhood, by contrast, has been a key player in Sunni Arab politics for decades, bringing a fundamentalist Islamist approach to a long battle against autocratic governments in Egypt and elsewhere. Along the way, extremists have left the Muslim Brotherhood to form splinter groups, like Hamas, that have sometimes veered into terrorism. But the summit came at a critical moment for both the Quds Force and the Muslim Brotherhood, which may explain why the two sides agreed to talk. When the meeting was held in April 2014, the Islamic State was tearing across the Sunni-dominated regions of northern Iraq. The Iraqi Army was melting away in the face of the terrorist group’s brutal tactics, and ISIS was threatening the stability of the Iraqi government in Baghdad. The threat of ISIS prompted the Quds Force to intervene on behalf of the Shia-dominated government of Prime Minister Nouri al-Maliki in Iraq. The Quds Force began leading Shia militias into battle against ISIS, but Maliki was widely seen as an Iranian puppet and had stoked deep anger and resentment among Iraqi Sunnis. He would soon be pushed aside. At the same time, the dream of the Arab Spring had turned into a nightmare. War was raging in Syria while in Egypt, the ouster of Morsi’s Muslim Brotherhood-dominated government had led to a new dictatorship under Sisi. Morsi died in an Egyptian courtroom in June after nearly six years in solitary confinement. Weakened by its losses in Egypt, the Muslim Brotherhood probably viewed an alliance with the Iranians as an opportunity to regain some of its regional prominence.