Book excerpt: On Liberty is the story of today's threats to our freedoms and a highly personal, impassioned plea in defence of fundamental rights, from Shami Chakrabarti, Britain's leading human rights campaigner On 11 September 2001, our world changed. The West's response to 9/11 has morphed into a period of exception. Governments have decided that the rule of law and human rights are often too costly. In On Liberty, Shami Chakrabarti explores why our fundamental rights and freedoms are indispensable. She shows, too, the unprecedented pressures those rights are under today. Drawing on her own work in high-profile campaigns, from privacy laws to anti-terror legislation, Chakrabarti shows the threats to our democratic institutions and why our rights are paramount in upholding democracy. 'Probably the most effective public affairs lobbyist of the past 20 years' - David Aaronovitch, The Times 'The undaunted freedom fighter' - Observer 'The most dangerous woman in Britain' - Sun