The American addiction for guns, is not based on all the dodgy people who happene to be around. if no one was allowed guns there would be fewer people around to use guns to scare people, the right to have a gun is based on a misunderstanding, or ignorance of what the purpose of the relevant Constitutional Amenedment was.
The amendment says A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed.
The meaning of this, in the context of the early years of the USA, when, with a small population spread over a huge area, and communications and travel was difficulty,was, that if there was a danger, the local governor could call up the militia, essentially a group like our territorial army and immediately have a body of armed men ready to serve their country. when, had he had to contact Washington and then wait for the cavalry to come over the hill, he could be waiting months, by which time the threat, whatever it was would have overcome them.
It was never intended to mean that anyone anywhere could have a gun for any purpose and act as a one man militia in their own favour.