Nukes for Iran

Why should Iran give up its nuclear ambitions? Its neighbours have nuclear weapons. An attack by the USA seems to be on the cards. For Iran to have nukes then is only sensible. Iran is a country with a democratically elected president and government. What right do other countries have to interfere in its internal affairs? How would Britons feel if we were told to dispose of our nuclear deterrent by the UN. Or how would Americans feel if they were ordered to close Guantanamo Bay... (Um...these are not terribly good examples are they?)
What about Britons being forced to spell things the American way? And Americans having to play rugby and cricket instead of football and baseball?
The purpose of nuclear weapons is to dissuade attack. If America tries to invade Iran, it would be a disaster of biblical proportions. What's needed is another Cold War in the Middle East, just to keep a lid on tensions until a new generation comes to power and diplomatic solutions have time to be worked towards.