News of what happened at Leytonstone, of course, spread all over the world, so relatives and friends from the States got in touch. After I assured them that I was okay, they then went on to ask why and how the Met dealt with a potential terror situation - without guns. It was so strange, so incomprehensible, something they could not imagine. That's because the USA is an armed society. Arms are the equalizer; the avenger; the explainer; the revenge; and your best friend.