I believe any country with the know - how and money is going to make an effort to develop nuclear energy sooner or later. I don't think it is any longer a question of "should they". Iran will continue it's efforts regardless of what the rest of the world thinks. We cannot stop them. I would say all we can do is acknowledge the effort and remain vigilant.
Nuclear energy should be developed in Iran, just not nuclear weapons. There must be some kind of international safeguard that allows nuclear fuel to be monitored, stored and disposed of properly throughout the uranium enrichment process. Monitors can ensure that Iran doesn't create nuclear warheads at the behest of Russia or China.
There are many ways to get Iran nuclear reactors that doesn't involve the kind of process that they are under taking there currently. Reactors and similar types of things don't require a massive enrichment of uranium to the degree that it is being done in Iran, and there are better ways.
I do not believe that a country like Iran should have the ability to develop nuclear energy. I think that Iran has proven time and time again that they are a country that cannot be trusted. And they are also a country that has not been able to work well with other nations.
Developed countries are recognizing the need to pursue alternative sources of energy, partly because they recognize the foolishness and danger inherent in the use of nuclear energy. Developing nuclear energy plants should be discouraged in developing countries like Iran because it has been shown to be not the best alternative. Iran should be encouraged to develop renewable source of energy, like solar and wind, which would not take them down the same road we have already traveled.