Introduction

Combatting terrorism has very long roots in the United Kingdom. Indeed, the Metropolitan Police in London was formed in the 1880s to combat the Irish Finian threat. Since then, there has not been a single decade when the terrorist threat to the United Kingdom has not been a significant priority for the security and intelligence community, even if the nature and focus of that threat have changed considerably. For the United Kingdom, then, terrorism is not a new phenomenon. A great many observers have written about the lessons learnt from various ‘terrorist’ campaigns – Palestine, Malaya, Kenya and Northern Ireland – and how the United Kingdom, therefore, has had a great advantage in dealing with terrorism. However, this argument hides a simple truth: Despite some similarities, the Islamist threat that emerged after 2001 has been very different, as has the response required from the intelligence community.

This chapter briefly recounts the evolution of Islamist terrorism and its perception in the United Kingdom from the 1990s, discussing the changes brought about following the 11 September 2001 (9/11) attacks. It considers how the United Kingdom responded to this threat, focusing on the intelligence community's role. This context is necessary to understand the focus of the chapter – the 2006 liquid bomb plot, intended to down a significant number of aircraft flying across the Atlantic. It considers how that plot was detected, the interplay between the intelligence community and the police, the relationship between British and American intelligence and, ultimately, how and why it was deemed an intelligence success.