Iran's nuclear program has been a source of global instability. No one believes that Iran is developing a nuclear capacity for reasons of energy dependence and their is a great risk of starting a war with Israel that could consume the entire region and cost many their lives. Ahmadinejad could have also spared his country the costly sanctions.
Iran had a very well known nuclear program that put a lot of countries at high alert in the middle east. Nuclear weapons should never be used on anybody based on how destructive they can be. While Ahmadinejad was president he should have weighed the cost of how negative nuclear weapons can be.
I think Mahmoud Ahmadinejad played his cards incorrectly when he was the Iranian president. In doing so, he caused the United States and other Western powers to impose crippling sanctions on the country that wound up hurting the citizens. He could have easily kept his seat as president if he thought more intelligently.
I definitely believe that Mahmoud Ahmadinejad should have lessened Iran's nuclear program while he was president. He could have done a lot to improve the country's image in the international world while he was president. But considering he was not exactly the most rational of world leaders, it wasn't a suprise that he didn't do anything about the nukes.
Ahmadinejad was persistent when it came to Iran's nuclear program and he insisted that program was for energy, not the country is open to inspection since Ahmadinejad is out of the picture. The problems in Iran were problems within their government. We can't sit back and say Ahmadinejad should have done X, Y, and Z.