Bowing to pressure from European trading partners, Iran stopped uranium enrichment today. This program was increasing the content of Uranium 235 in uranium ore to 54 percent (producing uranium that contains that percentage of the more volatile U-235 form of the nuclear material). This is far above the 5-10 percent needed for nuclear power plants. Normally, Uranium ore is only about .7 percent U-235. Anything over 20 percent enriched can be used for a nuclear bomb. But the most effective and reliable nuclear weapons use 80 percent enriched nuclear material. Iran has lied, for over a decade, about its efforts to obtain enrichment technology. Iran can buy nuclear fuel for its nuclear power plants, so it kept the enrichment program secret. For the only reason for having an enrichment program was to create weapons grade nuclear material. There is some doubt that the Iranians will keep any deal on nuclear weapons development. Although the Iranians have agreed to allow inspections by the UN IAEA, the Iranians have deceived inspectors before.