but could have easily carried in a bomb. Again, this is a theoretical threat

Heard a story of a British officer giving an American secret service officer the rundown of Westminster Palace in anticipation of an American president visiting. They asked why there weren’t any screens at the viewing gallery (or maybe about why there were??? One of the two) and the British officer cited an incident where Tony Blair had a pink powder thrown on him during PMQs. The American asked how they dealt with him, to which he got the reply “Oh we just arrested him after” The American was shocked. “What!? We would have shot him, that could have been anthrax for all that you know”