Mr Andrew, I do like your well backed argument. I agree of course. The problem is that rational, scientifically and ethically backed arguments against any part of their Consitution are felt by US citizens to be an attack on their identity and culture.
I could add the death toll in Europe and my small country (0,6/100k), but that wouldn’t change the force of the argument for them. I could add the number of mass shootings (156 in the US, 19 in Europe during the same number of years). It won’t help.
The poor sods are victim of cognitive dissonance (my truth is the only truth) and moral obesity (we are entitled to be the greatest).