Poor driving and rude driving are just that unless you have significant evidence of aggression directed at you as an individual.

With respect, introducing a weapon as the next factor seems premature, at a minimum.

When someone cuts me off, I just slow way down. And I hope that idiot / jerk / incompetent just proceeds away from me. This strategy has not failed yet.

I particularly hope the person is not injured in an accident in front of me because I really do not want to feel obligated to render them aid - but I hope that I would.

If the person does evidence directed aggression, then evasion by driving, a 911 call, and driving toward known law enforcement or manned security locations, would be priorities far ahead of reaching for a weapon. I would consider foot evasion if I had confidence of its success.

After exhausting those possibilities it may become a survival situation where the choices are few. If the person was pursuing in a vehicle, then my vehicle would be my first weapon of choice. If the pursuer was on foot and apparently unarmed, then improvised non-lethal weapons would be my choice. And if the pursuer was armed, close confrontation was unavoidable, and I felt my life or that of others was at risk - I would strike with the most powerful weapon at my disposal.