As a comment. In case I don't get the time or motivation to flesh it out, I'll use this as a place holder:
Registry is the path to confiscation. See great Britain, Australia, etc. Tests and background checks are the equivalent of poll taxes and literacy tests for voting. School shootings are extremely rare events, but the level of media coverage rivals that of a moon landing, so the perception is skewed to match a specific narrative. Also Kellermann's "Gun Ownership as a Risk factor for Homicide in the Home", rivals Bellesiles' "Arming America", for laughably flawed and biased methodology in every aspect of research and people seriously need to stop quoting numbers that have been completely debunked.