The threat of terrorism has escalated severalfold since terrorists struck the United States on 11 September 2001. Instead of an average of one attack by Al-Qaeda every year, post-9/11 Al-Qaeda and its associated groups stage an average of one attack every three months. Both before and after 9/11, Al-Qaeda successfully attacked or attempted to attack naval and commercial shipping of the US, its allies or its friends. After an aborted attempt to target USS The Sullivans in January 2000, Al-Qaeda nearly sank the state-of-the-art destroyer USS Cole in October 2000. Two years later, when a US warship failed to appear in a pre-designated kill zone of Al-Qaeda off Yemen, an explosives-laden boat piloted by an Al-Qaeda member struck a target of opportunity — the French oil supertanker Limburg.

As a learning organization, Al-Qaeda maximized its successes and minimized its failures. As the “pioneering vanguard of the Islamic movements”, Al-Qaeda also instilled in its associated groups the important belief that they must repeat its successes. The international alert and publicity generated by these two iconic attacks led Al- Qaeda and its associated groups to invest extensively in developing technologies, tactics and techniques for conducting maritime terrorist operations. This was confirmed by the recovery in Afghanistan of video tapes for Asian, Middle Eastern, African and Caucasian terrorist groups to study in depth both offensive and defensive maritime operations by governments as well as by other terrorist groups. The clips of US warships in the Gulf, marine police patrolling the Malacca Strait, and maritime attacks by the Liberation Tigers of Tamil Eelam, the masters of maritime guerrilla and terrorist operations, were among the 241 videos recovered from the Al-Qaeda registry in Afghanistan.

Our knowledge of terrorist intentions, capabilities, and their opportunities for attack, increased after the US invasion of Afghanistan in October 2001. Terrorist training manuals and attack plans specifically targeting naval and commercial maritime shipping in Asia, the Gulf and in the Mediterranean were recovered from the caves of Afghanistan and safe houses in Pakistan. Some of the training manuals both of Al-Qaeda and its associated groups, especially Harkat-ul-Mujahidin, demonstrated that the contemporary terrorist had developed extensive knowledge for conducting surface and underwater maritime attacks.