The rise of transnationalist jihadis and the shift from localism to globalism cannot be understood without contextualizing the alliance between two men, Osama bin Laden and Ayman al-Zawahiri, and the merging of their resources and talents. The experience and character of these two senior jihadis were complementary, and their combination was vital in the internationalization of jihad. Retracing the jihadist journey of bin Laden and Zawahiri and the evolution of their ideas and actions over time and space will illuminate the dramatic changes that occurred within the jihadist movement in the second half of the 1990s.

Since September 11, memoirs, diaries, and interviews with jihadis clearly point to the bin Laden–Zawahiri connection as the driving force behind the formal birth of Al Qaeda and its strategic decision to take jihad global. Although Zawahiri was not one of the three founders of Al Qaeda – bin Laden, Abu Ubaidah al-Banshiri, and Abu Hafs – by the second half of the 1990s he played a pivotal role in the rising network and had developed a close partnership with bin Laden. It is true that after the drowning of Abu Ubaidah in Lake Victoria, Abu Hafs became bin Laden's most trusted aide and defense minister, but Abu Hafs was bin Laden's military man, with no militia of his own and no intellectual or scholarly religious capital. In contrast, Zawahiri was leader of Tanzim al-Jihad, one of the oldest and deadliest existing jihadist organizations, and he became a leading theoretician of jihadism.