But visitors can seek reassurance in the fact that Britain's police and intelligence officials have been successful since then in foiling attacks on the capital.
While foiling tax cheats and identity thieves are certainly in the public interest, there is another side to the story, and it is the story of my clients who have experienced it.
The information is understood to have been obtained as part of an inquiry into possible leaks, after the news agency last year ran a story about the CIA foiling a Yemeni bomb plot.
They may even be aware that the rite of burning an effigy on November 5th (a tradition admittedly under threat from political correctness and the health-and-safety police) celebrates the foiling of a plot to blow up the Houses of Parliament.