Mahmoud Ahmadinejad's disputed re-election in 2009 triggered large-scale protests in Iran as supporters of the opposition candidate Mir-Hossein Mousavi took to the streets to protest.
Ahmadinejad's global importance now hinges on Iran's nuclear programme, which he has defended as an "inalienable right". Vehemently denying that his country is secretly building a bomb, he claims that the programme is peaceful, and enriches uranium for civilian power generation only.
This position is irreconcilable with that of the US and its allies, which have enacted a series of sanctions against Iran. As recently as August, a top US military official refused to rule out military action.
Ahmadinejad says he will not retreat "one iota" on the matter, which means he will stay at the top of the west's foreign policy agenda for the foreseeable future.
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