Although al-Qaeda and Iran sit on opposite sides of the Sunni-Shiite divide, and often denounce one another, they are not averse to cooperating. Osama bin Laden in fact noted in a 2007 memo that the Islamic Republic was his organization’s “main artery for funds, personnel, and communication.” With the death of bin Laden’s successor, Ayman al-Zawahiri, Oved Lobel argues that the terrorist group’s entanglement with Iran may grow even deeper:
[T]he next in line for leadership—assuming he himself is still alive—is widely agreed to be al-Qaeda’s long-standing military chief Sayf al-Adl, who has been based in Iran for decades. If anyone can revive the organization’s fortunes, it is al-Adl, and with al-Qaeda officials now on notice that Afghanistan still isn’t safe for them, many may choose to relocate to Iran. The relationship between Zawahiri’s pre-al-Qaeda Egyptian Islamic Jihad and Iran’s Islamic Revolutionary Guard Corps (IRGC), including its Lebanese branch Hizballah, began as early as 1991, eventually evolving into a deep partnership between al-Qaeda and Tehran.
This is where Israel could come into the picture. Almost exactly two years ago, Israel reportedly assassinated al-Qaeda’s then-number two, Abu Mohammad al-Masri, in the center of Tehran. . . . In recent years, Israel’s pervasive infiltration and agent network across Iran has allowed it to assassinate IRGC officials, military officers, nuclear scientists, and anyone else likely to pose a threat, including al-Qaeda leaders, practically at will.
As the U.S. seemingly has no similar network and would be very unlikely to conduct a strike directly on Iranian territory, it would have to rely once again on Israel’s agents to kill Sayf al-Adl if it became necessary to head off any potential attempts to reconstitute al-Qaeda there.