It remains to be seen whether the impending inauguration of Joe Biden as US president next week will quell the on-off tanker attacks in the Middle East.
Biden, set to assume office on 20 January, is said to be supportive of negotiating with Iran, in contrast with outgoing President Donald Trump whose administration waged a "maximum pressure" campaign against the Islamic republic.
But with pressing issues at home, it remains to be seen how, when and if Biden can quickly and easily calm the tensions that set off 18 months of attacks on commercial shipping.
"From what we are hearing, they are going to focus on resolving the issues internally," said Chronis Kapalidis, senior analyst at maritime security consultancy HudsonAnalytix, referring to Biden's priorities once he takes office.
Kapalidis said the new administration would look to tackle domestic issues such as Covid-19 and the economy while dealing with the fallout from last week's riots at the Capitol.
"That doesn't mean the diplomats and the people who are responsible for re-establishing the US as a leader globally won't start working from the first day," he said.
"More or less, they'll run at the same time."
In 2018, Trump pulled out of a three-year-old deal with Iran negotiated by his predecessor Barack Obama.
The multilateral deal, which included the US, EU, China and Russia, saw sanctions against Iran lifted in exchange for limits placed on the country's nuclear programme.
Withdrawal saw the US put sanctions back on Iran, including dozens against shipping companies, their vessels, their executives and those who do business with them abroad.
Retaliation
In what many considered retaliation, Iran allegedly sabotaged tankers in the spring of 2019 near the Strait of Hormuz — through which 30% of global crude oil passes — before moving on to bombings and the high-profile seizure of the UK-flagged, 50,000-dwt Stena Impero (built 2018).
Incidents waned in the autumn and winter. The calm lasted throughout most of 2020 before two tankers were bombed in the Red Sea with the same type of explosives used in the 2019 attacks. The perpetrators were allegedly Iran-backed Yemeni Houthi rebels. On 4 January, Iran seized the 17,400-dwt Chemi Hankuk (built 2000).
The tanker was seized over alleged pollution, but likely has more to do with billions in Iranian funds frozen in South Korean banks.
Is the deal salvageable?
It is widely assumed that Biden, who served as Obama’s vice president from 2009 to 2017, would seek to restore the nuclear deal known formally as the Joint Comprehensive Plan of Action.
It is unclear if Iran would support such a measure.
The country has taken steps to violate the deal, including resuming the enrichment of uranium and moving forward with plans to produce uranium metal, a component of nuclear weapons.
Iran's foreign minister, Javad Zarif, has reportedly said Iran would not renegotiate the deal but would come back into compliance if sanctions are lifted.
Chatham House distinguished fellow Paul Stevens said Iran is likely to be wary of the US and unwilling to give any more in renegotiations. He said hardliners in Tehran do not want to deal with the US under any circumstances.
"Unless Washington makes certain concessions in terms of sanctions, I don't think the Iranians are likely to want to renew it," Stevens told TradeWinds.
No votes in being nice
There is also the issue, Stevens said, of broader US sentiment toward Tehran influencing Biden's willingness.
"I think the reality is ... that there are no votes in being nice to Iran in the United States by anybody," he said.
Stevens did not believe tankers would be a target for Iran moving forward, casting it as a red line that could provoke a military response.
He also cautioned against the idea of the Houthis as puppets of Iran.
"I don't think much is going to happen, to be quite honest," Stevens said.
Kapalidis said if attacks continue he expects a "firm" response from the US, likely with Biden leaning on Nato.
He said if more incidents do occur, they would not be fixed to the end of Trump's presidency and Biden's inauguration.
"The reality is probably somewhere in the middle," he said. "It's highly likely that Iran will continue with these ... tactics."
