Ebrahim Raisi has been one of Iran’s hardest of hardliners, a fanatical and absolute believer in the Iranian revolution and its mission.
If he has died on a mountainside in the north of the country, as looks increasingly likely, it will be a major moment for the country and the region.
It will remove from the Middle East one of its toughest most uncompromising players.
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A man who launched the first direct attack on Israel in his country’s history and a hardliner on whose watch hundreds of Iranians have been killed in the brutal repression of recent women-led protests, Mr Raisi has a huge amount of blood on his hands.
His fearsome reputation goes back to the 1980s – a period that earned him the dubious soubriquet the Butcher of Tehran.
He sat on the so-called Death Panel of four Islamic judges who sentenced thousands of Iranian prisoners of conscience to their deaths during the purge of 1988.
Mr Raisi has personally been involved in two of the darkest periods of Iranian repression. And he was seen as one of the favourite contenders to replace the elderly and ailing Supreme Leader Ali Khamenei.
His accession to that role would have guaranteed years more of the same… and years more meddling abroad.
With Mr Raisi as president, Iran has engaged in more and more adventurous interventions beyond its borders.
With him in charge Iran has helped Houthis menace international shipping in the Red Sea; helped Hezbollah engage Israel in a seven-month duel over its northern border; aided militia in Iraq to attack, and in some cases kill, American soldiers; and helped Hamas fight its own war against the Jewish state.
After two years of unrest, economic failure and stuttering recovery from the pandemic, Iran is divided and weakened.
Its government has lost much of its credibility and support because of the atrocities it has meted out to its women.
Few outside the regime and its ranks of ardent followers will mourn a man who has overseen the death, incarceration or torture of so many.
Iranians may dare yearn for less repressive times without him. Outsiders will hope for a less troublesome Iran.
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But there are plenty more where he came from and the Supreme Leader is likely to find another hardliner to replace him.
The fear will be of instability in the run-up to elections. The government has been undermined by recent events, its Supreme Leader is unwell.
If Mr Raisi is dead, his government will try to secure the succession as quickly and smoothly as it can.
