I have never been there but I think it is because there is a tradition in the UK of police not carrying guns except for at airports. I don't know how they make it work but somehow it does and Japan is also similar. As for those five other countries carrying guns are embedded in their cultures just as in the UK not carrying guns are embedded in their culture.
Every culture is different.
Take it that you don't have any idea about the criminals over here. They don't carry guns because the UK isn't obsessed with every household having a firearm so armed police are not required. Hence hardly any gun crime, our police carry Asps, CS spray and some carry Tasers and that is it.
Occasionally you get the odd idiot with a gun but he usually kills himself before the police open fire.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.