"I'm for nuclear energy for Iran, if only because it will reduce the global warming trend. Sooner or later, no country will be able to forbid any other to get nuclear energy."

There are no countries which are forbidden nuclear energy. Iran was not forbidden nuclear energy. All countries part of NPT are entitled to get nuclear technology to be used for nuclear power, those not part of NPT weren't allowed to be given nuclear technology, but they could decide to develop the technology if the chose not to be NPT members:

"There are 188 sovereign states party to the treaty. However, two (India and Pakistan) out of eight confirmed nuclear powers (i.e., those who have openly tested nuclear weapons), and one unconfirmed nuclear power (Israel) neither signed nor ratified the treaty. One further nuclear power (North Korea) ratified the treaty, broke it, and then later withdrew. The treaty was proposed by Ireland, and Finland was the first to sign. In New York City, on May 11, 1995, the parties to the treaty decided by consensus to extended the treaty indefinitely and without conditions.

The treaty is often summarised as having three pillars: non-proliferation, disarmament, and the right to peacefully use nuclear technology."
http://en.wikipedia.org/wiki/Nuclear_Non-Proliferation_Treaty

Iran:
"The Iranian nuclear program was launched in the 1950s with the help of the United States. After the Islamic Revolution in 1979, the government temporarily disbanded the programme, then revived it with less Western assistance than the pre-revolution era. Iran's current effort includes several research sites, a uranium mine, a nuclear reactor, and uranium processing facilities that include a uranium enrichment plant. The Iranian government asserts that the programme's goal is to develop nuclear power plants, and that it plans to use them to generate 6,000 MW of electricity by 2010.[1] U.S. and some other nations' officials say the program covers an attempt to acquire nuclear weapons. As of 2006, nuclear power does not contribute to the Iranian energy grid."
http://en.wikipedia.org/wiki/Nuclear_program_of_Iran