Trump supporters going havoc

I am intrigued to what makes those Trump-supporters go havoc in the US now. Sure, I can understand that they are upset that their candidate lost; but how do you go from there - to storm the Congress? What drives a mob to do just that? What do they expect to achieve? I highly doubt it will change anything, except for making a worse climate between the sides. The psychology to it is just amazing. Any US and Trump-supporters here that could enlighten me?