As news of Iran's follow-through in drawing down its nuclear program, and the expected Western sanctions relief, circulated earlier this week, it reminded me of how long and complex the story of Iran's nuclear program truly is (The New York Times has an awesome timeline). 

The cars of assassinated Iranian nuclear scientists on display at the Non Aligned Movement summit in Tehran, August 2012 (Photo by Kaveh Kazemi/Getty Images)

As recently as 2012,  there was plenty of rhetoric about Israel, with possible assistance from the US, conducting a preventative military strike on Iran's nuclear facilities. A quick search shows the debate over whether to strike was both international — between Israel and the US — and on the domestic agenda of these countries as well.

Israeli Prime Minister Benjamin Netanyahu and Defense Minister Ehud Barak led the argument in favour of an attack, likely through an air raid by the Israeli Air Force (there were even rumors of Israel using an air base in Azerbaijan). Famously, the high point of the Israeli Prime Minister's campaign was a UN General Assembly appearance where he demanded the international community draw a 'clear red line' on Iran's nuclear enrichment activities. 

But at the time there was also speculation that the bluster of Netanyahu and Barak was really a ploy to try and force the international community to concentrate on the Iranian issue, as well as an attempt to ratchet up the sanctions regime. There was significant —and unusually open — debate within the Israeli security establishment, but it is not clear if the dissenting voices were real or manufactured.

It does appear that Israel and the US (even if it was being dragged in) were extremely close to a conflict with Iran in the first half of 2012, before the nuclear deal negotiations began in earnest. On 25 January 2012, the New York Times Magazine published an article titled Will Israel Attack Iran?, in which the Israeli investigative journalist Ronen Bergman concluded: 'After speaking with many senior Israeli leaders and chiefs of the military and intelligence, I have come to believe that Israel will indeed strike Iran in 2012'.

Five months later, former Mossad chief Meir Dagan told The Atlantic Magazine Netanyahu and Barak were 'very serious'.  Dagan added: 'I'm taking the threat of an Israeli attack very seriously'. Last year Barak apparently stated in interviews to his biographers that in 2010, 2011 and 2012 he and Netanyahu had 'planned to do it', but for various reasons the attacks had to be called off each time. 

Even outside of Israel, it seems the threat of war was real. Michael D Morell, a former deputy-director at the CIA, recently told The New York Times that 'Before the negotiations for the nuclear deal began . . . we were closer to war with the Islamic Republic than at any time since 1979'.

So what happened? Essentially sanctions, but also sabotage.

Yes, the international sanction regime had a significant effect in forcing Iran to the table because they bit hard. In 2011 Iran was exporting 2.5 million barrels of crude per day; by mid-2013 this had dropped to 1.1 million. Also, it should be remembered that President Hassan Rouhani was elected in 2013 in part on a platform of seeking sanction relief, as Iran's economy reportedly shrank 'by about 10% in the two years that ended in March 2014'.

But when the full history of this episode comes to be written, the role espionage played in the Iranian nuclear deal could well be the most interesting. A recent article by David Sanger lays out the long and complex sabotage program the US and Israel conducted against Iranian nuclear infrastructure in order to buy time for sanctions to take effect. The Stuxnet virus, released in 2008-2009, is thought to have delayed Iranian enrichment efforts for a year. The assassination of at least five Iranian nuclear scientists, likely by Mossad, had an effect. And as Sanger notes, the machinery the Iranians had bought to power their centrifuges kept exploding; they had been rigged by the US before being shipped to Iran.

Even with the limited information we have now,  it's clear the last 10 years of the Iranian nuclear program includes close calls, sanction dodging and black markets, espionage and obviously a patient and clever use of state power by the US. The history nerd in me is jealous of the historian that one day gets to pull it all together.