Do you think the Iran-Iraq war is any indication of their capability?
Even though it was 30+ years ago, do you think they have changed any of their fundamental deficiencies?
Before Islam, the Persian culture was one of the most advanced societies of the time. Now look where they are.
You really can't do business with them because they think it's fine to steal from Westerners...in fact anyone who is not Shia. They hold all Sunni muslims in utter contempt. They pirate software (which of course made them susceptible to certain computer viruses) and anything else that has copyrights in the Western world.
For many reasons discussed above, I think they may be technically capable of developing nuclear weapons, but fighting a war against an adversary who is competent at the tactical, operational and strategic levels is not something Iran is capable of doing, imho.
However, Iran has a population of about 82 million, many of whom are well educated. To put that number in perspective, the US population was about 132M at the beginning of WWII. Hence the Iran-Iraq war of the 80's was a war of attrition and Iran had the larger population.