The dramatic terrorist attacks in the United States in September 2001 all too clearly illustrated the threat posed by international terrorism. Understandably, politicians are provoked into taking tough measures to protect their citizens from terrorist enemies. In times of danger the civil liberties implications of such measures can easily play second fiddle to security needs. Indeed, we need look no further in our jurisprudence than the discredited majority decision in Liversidge v. Anderson [1942] A.C. 206. Recently, Lord Woolf has warned that “the mistakes which have been made in the past, in relation to internment of aliens at the outbreak of war, should not be forgotten” (A v. Secretary of State for the Home Department [2002] EWCA Civ 1502 at para. [9]).