Three weeks later, the foreseeable unfolded. The same boy, still unchecked, collided with a seventy three-year-old Greek woman inside the centre. She fell, striking her head and suffering a massive hematoma.

Ultimately, stress management is about doing better, when it matters, rather than about feeling better. The practical advantage is what separates those who perform from those who provide protection.

One critique of the personal protection market is that not all individuals can afford advanced devices.

Emergencies are rarely defined by the hazard itself but by how people respond to it. Yet most people and even policymakers operate under...