Had a rather disturbing event with a non-typical reaction on my part this morning while driving to work. I'm heading south on a main arterial street, in the RH lane of two lanes. There is semi tractor/trailer also travelling south in the LH lane. I'm doing the speed limit and the truck was going about 10-15 mph slower than me. It's an industrial park area so I am anticipating this truck driver will continue slowing and be turning left fairly soon. Well dickweed turns right, from the left lane, without signaling and apparently without checking his right mirror because I am about half a vehicle length ahead of his rear wheels. I jam on my brakes and his right rear wheels miss me by inches. Half a second later and I woulda been toast. Now the interesting part- I freakin snap. I follow him around the corner, pass him, and edge him over to the left curb stopping in front of him. I need to mention, I'm not delusional, I don't think I'm a tough guy but it did cross my mind that often times truck drivers are big rough guys. I didn't care. I fully expected he would take exception to how I stopped him and we'd be going at it. Well he rolls down his window and I'm just screaming and swearing at him, telling him to use his f'ing turn signal and mirrors and quit driving like a f'ing idiot. Luckily he nodded in agreement, looked like he knew he did something wrong, and kept saying yeah to everything I was telling him. So I get back in my vehicle and go to work still overloaded with adrenaline. WTF is that all about? Justified road rage? IdK but I do know I had absolutely no control over my actions. Pretty crazy.