This chilling 9-11 call is a great example.
In every emergency the people present are the first responders.
Ten minutes into the call, almost six minutes after the home owner is forced to defend himself police finally arrive. It takes them more than 12 minutes total to finally enter the home.
Notice too that the man is required to unload and secure his firearm before the house is cleared and before the police will allow him to open the door to let them in.
In the event there were still armed bad guys in the home this man likely would have ended up either being killed or taken hostage.
Your life, and the lives of your family are literally in your own hands in such an event.
Warning, there are things on this audio that may be upsetting to some people.
In the vast majority of cases, the police are not going to come save you, they will arrive after the incident is over to fill out reports and drag away the bodies.