TERRORIST attacks are fiendishly hard to prevent. Anyone can rent or steal a lorry and drive it at a crowd. Especially in America, it is all too easy to buy high-powered semi-automatic weapons that can kill scores of people in moments. Neither great planning nor great intelligence is required to carry out such attacks. Thus it seems likely that much of Europe and America will have to get used to acts of Islamist-inspired terrorism becoming, if not routine, at least fairly regular occurrences.

But even though the number of deaths from attacks is rising, the West has experienced this level of terror before. As a result of the Troubles in Northern Ireland and the actions of ETA, a Basque separatist group, terrorism was consistently deadlier in the 1970s and 1980s than it has been since.

Yet the chance of being murdered was small. During the 30 years of the Troubles, the annual risk for civilians of being killed in Ulster was about one in 25,000. Even in 2001, the likelihood of an American in the United States being killed in a terrorist attack was less than one in 100,000; in the decade up to 2013 that fell to one in 56m. The chance of being the victim in 2013 of an ordinary homicide in the United States was one in 20,000. Barack Obama was correct when he said earlier this year that the danger of drowning in a bathtub is greater than that of being killed by terrorists. Baths are a one-in-a-million risk. Even if the terrorism deaths in San Bernardino and Orlando were doubled to give an annual death toll, the risk would still be about one in 2.5m.

Read the full article here.