London bombings spurred anti-terror measures that some say went too far

After four home-grown suicide bombers killed 52 London commuters on July 7, 2005, Prime Minister Tony Blair vowed that Britain would stop at nothing to defeat terrorism. "Let no one be in any doubt," he said. "The rules of the game are changing."

Since the September 11 attacks in the United States four years earlier, Britain had made its anti-terrorism powers among the toughest in the Western world. Now they became tougher still.

"What 7/7 did was it made people realise that the threat was internal as well as external," said David Anderson, Britain's official reviewer of terrorism legislation.

After the 7/7 attacks, which occurred exactly 10 years ago today, police were given new powers and it became a crime not just to commit or plan for terrorism but to glorify terrorist acts.

The government moved to deport extremist preachers who had made their home in Britain. The ability of intelligence agencies to scoop up internet users' electronic data expanded vastly.

Civil libertarians sensed the spread of a Big Brother state, and waged legal and political battles that managed to water down or reverse some of the measures. But a decade later, Britons are more watched than ever. Last month's gun attack on tourists in Tunisia, which killed 30 Britons, shows the terrorist threat has not gone away, and could spur a new round of counterterrorism measures.