In the Middle East, the two most important cultures are the Egyptian and Persian civilisations. They have long stood as beacons of durable learning and contributed immeasurably to human progress. With the resurgence of “firstness” (for example “America First”), with all its ominous implications of narrow nationalism, there is a profound global need for a dialogue of civilisations. This call is not new, having originally been proposed by former reformist Iranian president Mohamed Khatami and most recently echoed by the grand imam of Cairo's Al-Azhar in a speech before the German Bundestag in 2016. However, while a broader conversation between the Islamic and Western civilisations is still of the utmost importance, so too is intra-Islamic dialogue. Egypt, with a third of the Sunni Arab world's population, and Iran, the biggest Shia country, could be the prime movers for reconciliation in the Muslim world and for regional stability. Relations between the two regional powers originally soured in the aftermath of the Iranian Revolution, when late Egyptian leader Anwar Al-Sadat gave refuge to the ousted former shah and signed the Egypt-Israel Peace Treaty in 1979. Efforts to reconcile the two countries have been made in the past. In 2004, one of the authors of this article, Seyed Hossein Mousavian, then head of the foreign relations committee of Iran's National Security Council, was invited to Egypt for a confidential meeting with Osama Al-Baz, then senior political advisor to the then Egyptian president Hosni Mubarak. After a day of negotiations in Alexandria, a package was agreed for the normalisation of Iranian-Egyptian ties. However, the agreement later met with rejection by top decision-makers in both Cairo and Tehran. Nevertheless, one of this article's authors, Yassin El-Ayouty, assesses that if diplomacy were tried again it would likely succeed. In a trip to Cairo in December last year, he found a groundswell within non-governmental organisations for Iranian-Egyptian rapprochement. The reasons for the warming up are diverse and include cooperation on terrorism. Mousavian has also found a readiness for such rapprochement in Tehran. Despite fear-mongering by some in Egypt about a so-called “Shia menace”, El-Ayouty, through his present work on a book on the “Sunni-Shia split”, has found no religious foundation for such a division. Egyptian and Iranian Islamic scholars have in the past reached historic accords on bridging Shiism and Sunnism. In the late 19th century, Egyptian sheikh Mohamed Abdu and Iranian cleric Jamaleddin Asadabadi cooperated on creating a pan-Islamic movement. In the 20th century, Iranian grand ayatollah Seyed Hossein Borujerdi and Al-Azhar grand imam Mahmoud Shaltout established cordial relations. Shaltout even issued a famous fatwa, or religious edict, recognising Shiism as a recognised Islamic sect. Al-Azhar had for many years prior to that fatwa taught Shiism as a part of its curriculum. Unfortunately, in recent years there has been an uptick in sectarian rhetoric from prominent Egyptian figures. Sheikh Youssef Al-Qaradawi, a prominent former Muslim Brotherhood acolyte, regularly engages in divisive bombast about Shiism and is a leading encourager of some of the most reactionary elements in the Muslim world. The late Iranian scholar Hashemi Rafsanjani once debated with Al-Qaradawi after he had made controversial anti-Shia remarks. Al-Qaradawi, however, is currently out of favour with Al-Azhar and living in Qatar as a Qatari citizen and a leading proselytiser of the puritanical and exclusivist Wahhabi sect. In addition to the religious and political tensions between Cairo and Tehran, Egypt's increased reliance on the Gulf Cooperation Council (GCC) countries — namely Saudi Arabia, Kuwait and the UAE — has also served to lower the chances of Egyptian-Iranian rapprochement. The Egyptian economy has for years been sliding downwards, a decline in fortunes due largely to a booming population (nearing 100 million). Interestingly, an important lifeline for Egypt has been loans from the UAE, which has covertly cooperated with Al-Azhar sheikhs against the Saudi Wahhabi sect. Egypt's hands-off stance in the war unleashed by former Iraqi president Saddam Hussein on Iran (1980-1988) was later reversed in favour of inter-Arab collaboration to stop Saddam from swallowing up Kuwait (1990-1991). This was followed by an apprehensive wait-and-see policy regarding America's 2003 war of choice on Iraq. The historic pendulum of Egyptian politics towards Arabian Gulf issues can be seen as emblematic of Egyptian diplomacy's aim to balance foreign relations. Such desire to bifurcate Egyptian foreign policy makes the resumption of ties with Tehran a necessity. There are grounds to be optimistic about a future Cairo-Tehran rapprochement, as is evident in the following facts: the negative reaction of the GCC towards the Iran nuclear deal found no tangible expression of sympathy in Cairo; the charges by America and some regional states about Iran's fomenting terrorism or instability find no echoes in Cairo; and the Egyptian role in the so-called Arab coalition against the Houthis in Yemen has been confined to safeguarding safe passage through the Gulf of Aden. In addition, Iran's role in support of the Syrian regime has now been directly bolstered by Cairo's recognition of the folly of regime change in Damascus or elsewhere; and Cairo's relationship with Riyadh has had its ups and downs. This has been especially so in regard to rising opposition by Al-Azhar to the Wahhabi stranglehold on religious practices and education in the kingdom. Egypt and Iran are the two most historically influential and leading civilisations of the Muslim world and, indeed, of humanity as a whole. Furthermore, any idea of a religious animosity between them today is grossly exaggerated. After all, it was the Shia Fatimid Dynasty that constructed the city of Cairo over a millennium ago in Egypt. Egypt and Iran are the respective powerhouses of the Sunni Arab and Shia worlds. Cooperation between them can play a critical role in managing regional conflict, alleviating Sunni-Shia sectarianism, and containing calamitous regional civil wars. Critically, Iran and Egypt also have a similar stance on terrorist groups such as the Islamic State and Al- Qaeda. As a result, Cairo and Tehran have a great historical responsibility to establish strategic cooperation to manage the devastating crises in the region. Seyed Hossein Mousavian is an Iranian former diplomat, now a Middle East specialist at Princeton University in the US. He is the author of Iran and the United States: An Insider's View on the Failed Past and the Road to Peace. Yassin El-Ayouty is an attorney licensed in Egypt and the US and a professor of law at New York University. He is the author of The New Egypt: From Chaos to the Strong State.