We would need a program on the order of the Manhattan Project in order to develop it any time soon. I have a feeling no one is willing to spend that much money on any project.
The private sector would be willing in return for a monopoly. The private sector has the smarts to accomplish the feat, it just does not want to take the risk of the technology and investment being confiscated by the government.
The ONLY reason the Manhattan Project was a success is because of the "Iraq Factor". We didn't know what atomic bombs Hitler had, or when he would them. So we got them first.