Smoke billows from the World Trade Center in New York, Tuesday 11 September 2001
(EPA/EMPICS)

What is the war on terror all about?

There are many kinds of terrorism. Some are designed to kill as many people as possible, like September 11 and the bombs in Madrid and Bali. Other times, terrorists don’t target the public at all. One night in 1984, the IRA blew a large hole in the Brighton Grand Hotel, aiming to kill Margaret Thatcher (apparently, she got out unhurt because she was so late going to bed). You don’t even have to blow things up to be a terrorist. In 1989, loyalist paramilitaries shot dead Belfast lawyer Patrick Finucane in his home. Was the man who killed Finucane a terrorist? Most people would say so.

The legal definition of terrorism covers all this and more. Since the 2000 Terrorism Act, terrorism doesn’t have to involve hurting people. You can get done for ‘serious damage to property’ if you do it for political reasons. There doesn’t even have to be any actual violence or damage: the threat of violence counts as terrorism too. What have al-Qaeda and the Real IRA got in common with people who write threatening letters to animal-testing laboratories? According to the law, they’re all terrorists.