SWAT behavior like this predates Iraq and Afghanistan. SWAT developed in the 1970s in response to the drug war and gang violence.
They are not used the way they said they were going to be. They are paramilitary and are not concerned with being peace officers. They generally shoot first and ask questions later. Would not be a problem if they were raiding known firtified drug houses and gang headquarters. It is a problem going after small time otherwise on their own persons (or getting the address wrong, etc). They also do not care very much when they do get a wrong address, it takes months and years for people to get restitution from the police for such offenses.
Not sure how you get restitution when they murder someone.