It’s just shocking. I have tons of issues with police, but I never doubted their bravery in a crisis and willingness to put their lives on the line. It’s like firefighters hiding behind their truck instead of going into a building.
In a hostage situation, you don’t go in guns blazing. But the moment you hear gun shots you have to go in.
FWIW, my wife is a high school biology teacher in Florida. She’s getting a lot of messages about safety now and they are constantly (every period) sending someone to check that classrooms are all closed and locked while class in session. Lots of police presence too, partly due to pranks and threats.