how to deal with my young adult son

Hello everyone, I am new to this website and I hope your input can help me.

My 20 yr old son has not show up around the house during the last two days. He left after my wife told him a few things he may have not wanted to hear. It appears our son refuses to gain independence and be responsible for himself. He graduated from High School, then took a few months off, he later went on to attend a technical college for a couple of semesters. We helped him the most we could with this, both emotionally and financially. He quit on the second semester, said it was too though for him and wanted to take a semester off. He came back home, he takes a month or two before he finds a part time job. He keeps that job for two or three months and then quits. He is been without a job for a month or two now and we see no effort from him to find another one soon. I need to mention that my son loves to drink beer and maybe smoke pot here and there. He doesn't make it obvious, but I know. He is been spoiled in too many ways and because of that I know I am responsible for some of his behavior. He is also been in jail a couple of times for minor things and wrecked his and my car in the past.

I want to help my son and I wish I could get close to him, he seems lost and depressed. He does not talk much and I am not a very affectionate father. I don't know what kind of inner problems he has, his actions are not of a responsible 20 yr old. Tolerance and patience are not qualities I have, however, I have bent backwards on this regard because of my wife. It is because of my lack of tolerance and patience that I prefer to let my wife deal with him. I am sure he knows I disapprove of his behavior and knows exactly what I think about it and maybe that is why he never comes to me for advice. I don't know if I should come down on him hard and tell him to clean out his act or else leave the house. I don't like to see my wife depressed and worried about him so much. I can also try to be understanding and try to get through him. What will be the best approach in this circumstances? All I want is for him to have a full time job, or to go to school, the armed forces, college or other type of school. He seems to not want to do any of that. I just want him to be a normal and happy guy and not the way he is right now.