I would like to add my contribution to this thread 🙂
Everyday, Scotland Yard, Met police and Government officials recieve threats. In 99% of the cases these events never occured.
The administration knew that at this point it was not a question of IF London will get a terrorist attack ; It was a question of WHEN.
Hence, drills are the order of the day in big cities like London. If on that dreaded day last week, officials recieved a tip-off on the bombs what would you expect them to do if by the statistical ratio of Threats/ Bombs is out-balanced by scares (Just like Birmingham)
If you are expecting the Government to respond to threats in the same manner the evacuation was manouvered in Birmingham, we might as well not go out at all and stay at home.
A friend of mine from Birmingham told me that it was like that film - 28 days later.
Empty streets and nobody around.