To be completely frank and honest, there was nothing anyone could do from the moment JP decided he was going to do this, to the time he did this.
Everyone did their best, and while we can look back and see things we may have done differently, hindsight is always 20/20. Yes, we should look at, and examine, the series of events, but we should also always remember that we were NOT there, we did NOT have the pressure and the insanity in our faces, and we did NOT watch two children get brutally murdered by hatcheting and then explosions carried out by their father.
Josh Powell would have done this, period. It is luck, pure and simple, that we are not talking about a third murder (the S/W), or third and fourth murders (the Coxes).
I don't care how fast LE responded or didn't respond. They would never have been able to stop JP from igniting the blasts. Even if they were right outside, he would have done it.
If the 911 operator was a pure idiot, JP still would have done it.
If the 911 operator was able to send out squads right then, JP still would have done it.
If the kids had entered after the S/W, JP would have done it.
If visitation was not allowed, JP still would have done it, but at the Coxes' house.
It was gonna happen. From the moment when JP made up his mind this was how it was going to end, it was going to happen.
The responsibility of this lays only on JP. Not the social worker, and even if the 911 operator is a complete idiot, it's still not his fault. There were no actions anyone could take, even with dispatching immediately everything LE had including SWAT and HRT, that was going to stop JP.
JP was going to do what he did.
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Herding Cats