Nork Nukes.

The North Korean regime has it appears tested a nuclear bomb, one aspect of the reports puzzles me though, the explosion was the equivalent of 550 tonnes of TNT which is a very small nuke, far smaller that the Hiroshima bomb which was 15000 tonnes. The force of the World Trade Center collapse was equivalent to 600 tonnes of TNT and no nuclear weapons were used then. So either North Korea have very little nuclear material to use in tests or they have simply exploded 550 tonnes of TNT and claimed to have a workable nuclear bomb.