I can't debate without getting emotional
Basically, I can't debate without getting emotional, and I really, really hate it. It makes me feel like some jerk who can't control their emotions, especially when I get so angry I can't properly explain my side of the argument. The other person usually doesn't get emotional, and is calm, and has a smug look on their face because they got me so fired up, so it makes me feel like a complete fool who can't control their emotions. I find it kind of ironic, considering that I've always respected people who would talk politics with someone without getting emotional...
So, is it normal that I can't debate without getting emotional? What do I do to stop getting so emotional, and respond with a clear head?