Police have become militarized in the context of being fearful that every single civilian that they interact with could be armed.

As such, they treat every interaction as potentially lethal and are quick to escalate.

Clearly, some are just belligerent, aggressive assholes. But many of the them are just over-reacting unnecessarily because they think every single movement is towards a gun.

Here: http://useofforceproject.org/#project

I was listening to a Pod Save America podcast this weekend and they had DeRay Mckesson on to talk about direct correlations of certain use of force policies and rates of death of citizens by police. It’s the Justice for George Floyd episode and the maybe 15 minute segment was really interesting. The above link has the 8 suggested policies for cities to implement to reduce death. Just hit the link above and scroll down.

Pod episode: https://crooked.com/podcast/justice-for-george-floyd/

is about control on who can legally own weapons and what type.

We have always been a gun culture. From peace bonding in the wild west gun control has been a long standing issue.
Police have hated domestic calls forever because they just don't know if guns were in the house. hat really hasn't changed.
What has changed is the police response to that fact. First the gang wars of the 90's and then 9/11 moved the police training to a more military stance. While the 60's and 70's had a little of that, in the end that was more of n institutional top down directed from the political leadership and less as a response to any change in the actual police culture. Indeed to an extent both the police and the protesters saw those confrontations as more of a bar fight then a battle. There was a certain amount of its just business it the confrontations. While some had some tragic results and the King assignation led to some very tense moments for the most part the political leadership was just as happy to keep it confined to "their" areas. With RFK the mood shifted and took away much of the underlying animosity, so it was easier to shift back to baseline.
But in the 90's the shift was much more internal, we are still paying for that cultural shift as most of the longer serving officers and all of the top ranks have come within that culture.

But getting back to guns. Police training can change enough to minimize those confrontations and with support the entire concept can change. Right now police see themselves as having to resolve the incident at the point of contact. Just shifting that to stabilizing the situation while experts arrive, would dramatically change the dynamic. The training emphasizing situational triage, with follow up support.
The other thing is that while the police force has been militarized, it was only partially so. The military especially with officers and NCOs features a lot of cross training. Indeed your secondary MOS or SSI can be a real determinate in your ability to be promoted. Extending that and including a hefty dose of continuing training would go a long way. It also gives management another way to weed the ranks.

Unneeded by military but paid for with over budgeted military budget weapons and vehicles to police around the country.

I lived for ten years in a small rural town of 2,500 people almost zero crime of any sort and was shocked the day I saw our one police guy walking down the street like he was ready for Iraq.