The FBI knew about this cat for awhile. The bombs were simply more powerful than expected and killed 3 people and injured many others ... maybe the agent who supplied the brothers with the bombs was a double agent and put in dynamite instead of a firecracker ... somebody has some ‘splainin to do... just sayin ...
Who would take all the risks to knowingly plant such an underpowered bomb?
It's not like the FBI has no history of such shenanigans.
SOMEONE provided them with inert explosives!