France says thank you: the red carpet is rolled out at the presidential palace for four passengers who prevented a bloodbath aboard a high-speed train linking Amsterdam to Paris on Friday night. In our post 9/11 world, what can and should citizens do? Is it up to the government to tail every potential jihadist? Do you bring back border controls on the continent? Or would that set back European unity and play into the hands of those who want to turn Western democracies into surveillance states?
