The threat to America and its allies is greatest in the Middle East, but Tehran has ample options when it comes to taking revenge

Iran has spent decades preparing for a moment like this, developing methods and networks around the world that give Tehran the widest possible choice when it comes to taking revenge.

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In the weeks immediately after the airstrike that killed Iran’s most powerful general, the threat against Americans and their allies will be greatest in the Middle East, but the risk will balloon out across the globe over the months and years to come.

Any US outpost in Syria and Iraq, military or diplomatic, is vulnerable to attacks, likely to come from Iranian-backed militias linked to Kata’ib Hezbollah, which has served as Tehran’s most reliable fist in Iraq. In Iraq, there will be even less protection from the state, which is furious about the attack outside Baghdad airport.

The second ring of possible reprisals could follow an already familiar path, targeting oil shipments through the Persian Gulf. The leadership in Tehran will be conscious that one avenue of revenge against Donald Trump would be strike at his chances of re-election. An oil price spike, coupled with a backdrop of global instability and US vulnerability, would certainly hurt his campaign.

In Afghanistan, Iran has longstanding ties with Hazara militias and solid basis for operations in Herat.

In Lebanon, Hezbollah has long been Iran’s right arm, and can strike Israel and US regional interests at any time. And Hezbollah has networks much further afield where there are pockets of Lebanese Shia diaspora, for example in Latin America and West Africa.

Iranian intelligence has carried out assassinations in Europe, and there are a string of other attacks globally in which Iran or Hezbollah is suspected but not proven to be involved.

US intelligence certainly believes Hezbollah was behind the bombing of an Israeli-Argentinian cultural centre in Buenos Aires in 1994, and the bombing of a bus full of Israeli tourists in Burgas, Bulgaria, in 2012. The CIA was also convinced that Iran was involved in the bombing of Pan Am flight 103 over Lockerbie in 1988, in reprisal for the accidental downing of an Iranian airliner, Iran Air 655, five months earlier.

While Tehran has ample choices, it also has limitations. It will want to avoid triggering an all-out war with the US and its allies. It may now decide to build up a covert nuclear arsenal, no longer bound by the 2015 nuclear deal which Donald Trump walked out of. It would be harder to go down that road in the middle of a firefight. And each act of retribution could use up the political capital Iran has around the world, most importantly backing from Russia and China.

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But while Iran is likely to choose its targets carefully, with an eye to deniability, there is little doubt that reprisals will come at a time and place of Tehran’s choosing. The constant sense of insecurity that Americans and allies will feel will be part of the revenge.

“I frankly have never seen the Iranians not respond – tit for tat. It’s just never happened,” said Robert Baer, a former CIA officer. “It’s so in their DNA, [as is using] a proxy, which makes it more difficult to respond to. And their options are unlimited.”