Autism Spectrum Disorders themselves absolutely do NOT predispose people to violence, although they may make the world overwhelming and a harder place to understand. ... http://www.autismspeaks.org/what-autism
Having another disorder present could make it that much harder to control the symptoms and reach your child though.
I commend you for having plans in place! You are definitely doing right by your children!
I think mental health care in this country sorely needs to be addressed. I'm also glad you aren't teaching your son to use guns, or keeping them around the house. I think children shouldn't have to be around that kind of thing, especially when you have to worry about their safety and self-injurious behavior so much.
You are a good mother, and facing such a complicated and difficult struggle. Your son is lucky to have you-- and don't forget that you are helping him immensely by being so loving and involved, so keep up the good work, no matter how hard it gets!!
Thank you for sharing your experience!