Who, besides the gun lobby, the politicians owned by the gun lobby, and the gun-fetish nuts who worship the politicians owned by the gun lobby, wants to life like this?

No one. Not even the folks you name. Any more than people who value the First Amendment want there to be Nazis, or the people who think we ought to have cars want there to be auto accidents. But if you give the public the right to do something (or the license or privilege or whatever you want to call it), some individuals will end up misusing it. They don't want to give up something that they value - and think is valuable to society - solely because it gets misused.

You've spent countless hours discussing this issue with the folks on the right, how much progress have you made?

Great progress - but I think you misunderstand why I talk to people on the right. I don't do it to change their minds. No one's mind is ever changed on the internet. I do it so that I can hear what they have to say. So I can understand their point of view. It's my way of inoculating myself against what happens when judge people that we disagree with based on what their critics say, rather than speaking with them directly. I try to gain a better understanding of what other people in the world think of these things and why they think that way, including - and indeed especially - people who I disagree with.

What changes are they willing to accept to stop American children from being shot day after day after day?

If you could come up with a policy that could stop that from happening, but not significantly limit the values that they want to protect, they'd probably accept it. The problem is that most of the things that are "common sense" gun regulations are unlikely to stop the mass shootings you're referring to, and the sorts of things that would stop those mass shootings end up approaching disarmament. There's not a lot of middle ground, so they defend the thing they believe is very important.