Do you think the driver the OP is talking about is a logical person? Hell no! So...I'll ask again... If you "showed", and he's not logical, now you've just further pissed him off. See how that works? Now, instead of him acting like he's going to kill you, he just may and take it all the way. All you did was antagonize him and escalate the situation. He's driving a truck, you're on a motorcycle, he's not logical, you show your pistol, he puts you in the ditch, you lose. Let him pass. Have a smoke. Report his tag. Deal with the situation if he stops when you stop. This is the wisest decision.