Immunity for diplomats Watch
Obviously purely hypothetical but what would we do with the American ambassador in london if the US launched a nuclear strike against us? Would we have to let him go?
But these Japanese are so strick, and they treat us as common foreigners so there's hardly no difference between having or not having this immunity : )
The Queen isn't above the law, she is the law!
Basically, persons having diplomatic status cannot be prosecuted in the host country where they are accredited; they can however be declared "persona non grata" and expelled.
During WWII however quite a few diplomats were interned in their host country. .