In the 1983 movie War Games, a young Matthew Broderick hacks into the US nuclear weapons system. The movie represented the fear - popularized at the time - that computerization brought with it a serious security threat.

Hacking is great headache for IT departments, especially in the political world where strong political views at work. In 2003, the Labour Party website was hacked by people opposing the war in Iraq. In 1999, several US government websites were hacked. Databases and information sources are hacked all the time.

In Californian universities last year, university ID card systems were hacked, resulting in the details of over 1,000,000 students being released. George Mason University recently had 30,000 student records nicked from their ID card database. Similarly, the ID card database at the Georgia Institute of Technology suffered from 57,000 people's details being stolen, and the University of Texas at Austin had 55,000 records stolen.

The reason identity card databases are attractive to hackers is because the information on them is valuable. The UK's proposed national identity card database is supposed to make us feel safer. But the possibility that a copy of the database could end up being sold to Al Qaeda does not give me a great deal of comfort.