If you compare the standards to let’s say: Switzerland (2 years in the academy, the candidate must graduate with a diploma in policing. The first year is theoretical: mainly in the classroom learning about law, tactics and de-escalation. The second year is spent on the job in practical field training with a respective police force).
While police training in the US varies on state: but it’ll last up to 16-21 weeks (it’s pretty bad) before they’re sent on the streets, no wonder why you hear about cops resorting to violence first rather than a de-escalation. There’s an example from Norway where cops didn’t point their guns at a drunk guy, instead they laughed with him.
Both Norway & Switzerland DO NOT have qualified immunity for officers, meaning they are subjected to the same laws as every other citizen. But apparently the USA likes to consider cops above the law via qualified immunity (which is a reason why you barely hear an American cop being held accountable for their actions).
The responses are different: since US cops are like “GET DOWN!” or “DROP YOUR WEAPONS!” while Norwegian cops are like “Please, stop doing that” being said in a more pacifist tone that doesn’t evoke hostility (that’s an issue you hear from American cops, as they shoot first rather than trying to talk their way out).
Part of it is a cultural difference. There’s a formal training and apprenticeship program in Switzerland to become a waiter. The USA relies more on informal on-the-job training than formal education in many fields. In a large, professional police department, it’s often the case that a new hire will be assigned a field training officer for a while; that’s likely to be longer for someone without experience.
The higher level of violence isn’t just lack of training. Some of it is cultural, based on an “us vs. them” mentality. Some of it is based on actual dangers; people in Switzerland pretty much never respond to a traffic stop by shooting at the police, but that’s not a rare occurrence in the USA.
In the United States, in many areas, shoddy and spectacularly cheap on-the-job training is just another low-value thing that is more highly prized than formal education.