would slavery have ended without the Civil War? It seems unlikely.
Now can we pass substantive gun measures that will reduce gun violence in America without having another Civil War? Probably... But I doubt some of the gun advocates would give up any of their arms willingly.
How many times has President Obama -- whom I voted for, mind you -- suggested following either the Australian or British examples? E.g., where Australia and Britain confiscated weapons from legal owners.
In both NYC and CA, several small-scale confiscations have occurred.
That list goes on. And outside of outright confiscation, the gun-control crowd pushes nothing but more limits, more bans, and more asinine rules, all of which only serve to harass gun owners in exchange for zero measurable improvements in public safety (see the final report on the last Federal Assault Weapons Ban for more details on how utterly ineffective it was).
Like the State of California requiring a technology that is impossible under our current understanding of materials engineering in every new model of pistol sold. The result? No new models of pistols can be sold in California, and if a manufacturer updates an older model (say, to correct a safety flaw), then that pistol becomes banned, too.
If you want to know why gun owners -- and the NRA -- aren't budging an inch, the reason is simple:
Gun owners do not trust gun-control advocates, because gun-control advocates have repeatedly acted in bad faith.
It's not just the adoption of simple measures, though. There is a lot of resistance to wider-spread bans that are kinda just waiting in the wings ( https://en.wikipedia.org/wiki/Arms_Trade_Treaty ) to remove the self-determination and ability to self-arm. Sure, a lot of kooks are the ones resisting, but there are legitimate concerns there. Those bans are made possible by slow harmonizing measures, as weapons are restricted bit by bit by bit.
The basic problem in all of this is that the lies have been pervasive on both sides, and have been egregiously so in the case of proponents of gun-control measures. The phrase "assault weapon" was adopted literally to ban weapons that looked scary or military irrespective of their functional abilities. The phrase "commonsense measures" is specifically done to make a massive erosion of freedoms seem noncontroversial.
The entire posturing of gun control has been to either fear-monger or to smear as ignorant people who appreciate the value of retaining their right to self-defense and to do with their property what they will.
EDIT:
Loathe as I am to mention them, Breitbart has a useful quote showing exactly the mainstream politician talking about seizing weapons:
When those publications are as generally biased and nutzo as they are, I feel the need to disclaim referencing them even for direct quotes and facts. They had the information I needed, but I still don't want to act like they're gospel for anything else!
As for the data mongering, your link notes that (ignoring gang violence), there have been only 3, not 136, shootings this year. It's a bit curious that such a large order of magnitude change can be had by changing the definition slightly--and yet, it's nearly always the more dramatic number reported and reported as an imminent threat!
Now can we pass substantive gun measures that will reduce gun violence in America without having another Civil War? Probably... But I doubt some of the gun advocates would give up any of their arms willingly.