I have a nephew who is age 52 and his parents are deceased. He is high functioning Asbergers and lives alone in an apartment. My family, his aunts and uncle look after him. Plus his church helps out too. I am retired and go see about him once a week and take him to the store and for doctor's appointments. He has advanced diabetes and has lost a leg and uses a walker.
He was teased and bullied all through school. He really had a hard time in school because he was fat and strange, so he was ridiculed and bullied.
He has a lot rage in him and since he became a tea party follower, he directs his range towards the Democrats. He says he wants to kill the president and all the top Democrats. He will say he hopes we have another 9/11. He told me he wanted to get a gun. This will never happen because my sister and I control his bank account and pay all his bills because he is not capable of doing it himself. So he could never purchase a gun. Plus he is physically unable to carry out any threat since he can hardly walk. When he starts on a rant, I just tell him I won't listen to his crazy talk. I know his father (my brother) had gotten him some counseling when he was alive. I used to take him to lunch, but he told me he didn't want to go to lunch with me anymore. I know that is because I am a democrat. He still goes to lunch with my sisters, they are republicans. Go Figure.
I think a lot of Asberger's rage probably came from their experiences in school where they were teased like my nephew was. They do not have the same emotional reaction to things that a normal does and don't handle any emotional conflict well. He is obsessed with the weather and writes weather reports about 4 times a day and tracks all the tornados and hurricanes. I put $50 in his paypal every month so he can buy storm videos which he watches all the time. When he is worried or upset, he will start talking about a big storm hitting us.
If he were not in such poor health and did not have any physical disabilities, he could probably be dangerous.