Alexander Hamilton is now famous because of the award-winning musical which bears his name. But as a key founder of the United States constitutional system, he wrote in the Federalist Papers a prediction which resonates today: “Safety from external danger is the most powerful director of national conduct. Even the ardent love of liberty will, after a time, give way to its dictates … To be more safe [nations] … become willing to run the risk of being less free.”

In the 20 years since 9/11, Australia has enacted more than 130 pieces of national security legislation. Many of those laws created new criminal offences and exceptional investigative powers. While often controversial in principle and almost always contestable as to their terms, they seem to have become permanent.