I understand what you mean when you say that you know what you want, unfortunately he's saying that he's not sure. Don't you want him to be sure? You have to give him the space he is asking for because the botXXXXX XXXXXne is you can't force him to take this to the next level, he has to want to do that himself. It's natural for someone to feel hesitant after they've been hurt, and if they feel pressured by the next person, they can start to mistake the pressure for something else....they can start questioning how they really feel and start to put the distance between you. Just give him the space and try to stress out. When he sees that you are relaxed and not agitated or trying to push him in a certain direction, it's highly likely that he will go in that direction on his own.
If he doesn't....then at the very least you will know where the relationship stands, and you will see that either he is meant to be for you or not. I don't think that him feeling this way should throw up red flags, but that you should always understand that things can happen. Nothing in life is perfect, we have to enjoy and appreciate the good things we get in life and not spend out time worrying about the bad. Nobody wants to get hurt, but it happens....its how we deal with the hurt, and how we deal with our fears of loss, that makes us the people we are. Just like he is showing fear, you are showing fear and all that can do is push you further apart. Let him know if he wants to take it slow, thats fine with you, and really mean it, and see how things go.
I welcome your thoughts, let me know if you want to talk more