Think it through.
This wasn't a random road block, these were federal cops who were there for a specific purpose. I have little doubt that they had been told who was in that truck.
The guy had done at least one interview where he stated he would die before going to jail.
He was known to be armed.
He tried to run the road block. it looks to me that he actually ran over one cop in doing so.
We have no audio here, but it's safe to say that commands were being given continuously.
And he makes a move that looks to be going for a holstered sidearm.
Well, play stupid games, win stupid prizes.
If I, as a normal citizen who isn't wanted for anything, came up on a road block, decided to blow through it & run over a cop, I wouldn't give myself very good chances either.