Preface for the following book: On 20 October 2014, a terrorist drove his car into two members of the Canadian Armed Forces, killing Warrant Officer Patrice Vincent. Two days later, another terrorist murdered Corporal Nathan Cirillo before storming Parliament. In the aftermath of these attacks, Parliament enacted Bill C-51 — the most radical national security law in generations. This new law ignored hard lessons on how Canada both over- and underreacted to terrorism in the past. It also ignored evidence and urgent recommendations about how to avoid these dangers in the future.For much of 2015, Craig Forcese and Kent Roach have provided, as Maclean’s put it, the “intellectual core of what’s emerged as surprisingly vigorous push-back” to Bill C-51. In this book, they show that our terror laws now make a false promise of security even as they present a radical challenge to rights and liberties. They trace how our laws repeat past mistakes of institutionalized illegality while failing to address problems that weaken the accountability of security agencies and impair Canada’s ability to defend against terrorism.