> 5. They live in the US.
This is not factual. The Lankford study generally cited has been shown to ignore most non-US mass shootings.
https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3238736
Lankford’s study reported that from 1966 to 2012, there were 90 public mass shooters in the United States and 202 in the rest of world. We find that Lankford’s data represent a gross undercount of foreign attacks. Our list contains 1,448 attacks and at least 3,081 shooters outside the United States over just the last 15 years of the period that Lankford examined."
Data available: https://crimeresearch.org/data/
Yes, the US has a problem with gun violence, mass shootings, and suicides. No, it isn't unique to the US, and gun ownership isn't correlated (at least with the murders and mass shootings).
"The US ranks 58th in attack rate and 62st in murder
rate. Norway, Finland, Switzerland and Russia are major European countries with at
least 45% higher rates of murder from mass public shootings than the United States.
The rates in Pakistan and India are respectively 555% and 76% higher than the US
rate."
> The solution is to ban guns, full stop.
Similarly inaccurate:
"Lankford’s claim that higher rates of gun ownership are
associated with more mass public shooters completely disappears when this more
complete data on mass public shooters is used"