Really big but not a high order explosive IMHO. You can see the RV of the left side of the street.
I believe the stop light got hit by something and fell. But notice that the pole itself and the sign remained intact. The trees just a few yards away from the RV did not even move or had a branch broken. Same goes for the BB King’s sign on the right and the weak-ass no parking/tow away zone sign on the left.
The effective radius was short and it degraded quick. This being a narrow street helped create the structural damage, but I believe the shockwave was under the speed of sound.
But I am far from a bomb expert so take it the customary grain of salt.
And based on the actions/behaviors of the ATF and FBI crime scene units, they don’t appear to have found any explosives at the guy’s house.
They didn’t evacuate anyone in the neighborhood, and I’m not sure they even evacuated the other half of the duplex he was living in.
The “RV flooded with propane” hypothesis seems at least plausible, and involves minimal procurement issues.
The box truck (apparently sans explosives) supposedly playing a similar message is an extra puzzle; I have a speculation (the bomber could have placed time-delayed warning players on various vehicles), but no actual information.
The jackass in the box truck was just being a jackass. Either him, or the 17 year old with him, thought it would be funny to play the evacuation message over a PA first at a gas station and then outside a church during Sunday services.
It’s the literal fire-in-a-crowded-theater thing.
Ah. Freelance idiot copycat; no cleverness nor investment required. Makes sense, in a senseless sort of way.
LOL. I may have to steal “Freelance Idiot.”