Why Iran is scarier than North Korea

The picture is of the mushroom cloud over Nagasaki. This explosion was made with a plutonium based fusion bomb, the same type North Korea tried to explode a few weeks ago, but failed. Even though radioactivity was detected, that was more from the dispersion of the partially fissioned and unfissioned plutonium than from a successful fission bomb, such as the one shown to the right.

In other words, the North Korean bomb was a dud. The reason it failed is that plutonium bombs are hard to make. Plutonium fissions so quickly that conventional explosives have a hard time compressing the plutonium into a small lump for a long enough time to allow a significant amount of the plutonium to split and release all its energy. An improperly built plutonium bomb blows itself apart too soon.

Creating a plutonium bomb requires complicated machining and advanced detonator technology. But plutonium is created in a nuclear reactor, so it was readily available to the North Koreans because they have a reactor, and can use it to convert uranium to plutonium.

In the World War II the U.S. exploded three fission bombs. The first was a test of a plutonium bomb to be sure it would work. The second was the uranium bomb exploded over Hiroshima, and the third was the plutonium bomb over Nagasaki. The uranium bomb was never tested prior to use in combat. Uranium bombs are much easier to manufacture, once you have enough highly enriched uranium. In the case of the Hiroshima bomb, it was just assembled, and tested in combat. The problem is that the highly enriched uranium (HEU) needed to make the bomb is very difficult and expensive to make. It requires special devices such as a calutron, which can only make a small amount at a time, or very high speed centrifuges, which are a complex technology and difficult to keep clandestine. Still, it is what the Iranians are working on. Once they have enough HEU, the rest of the assembly of the bomb is not difficult.

Also, North Korea is surrounded by countries who are highly motivated to keep them from producing a bomb, especially China, who have significant influence on North Korea. Iran has enough oil revenue to be free of influence of its neighbors if its neighbors do not act in a very aggressive manner to keep the bomb out of the hands of the Tehran regime.

North Korea, even with plutonium in hand, is not as great a threat as Iran who are actively enriching uranium.