Qassem Soleimani: Killing of Quds Force leader marks new low in US-Iran relations

Analysis: Mood between Washington and Tehran has darkened since Donald Trump pulled US from 2015 nuclear deal

The targeted killing of Iranian Maj-Gen Qassem Soleimani by US forces represents just the latest escalation in Donald Trump's long-running campaign to contrast himself with his predecessor by taking an increasingly aggressive posture towards Tehran.

Mr Trump took office in 2017 having promised to pull the US out of the 2015 Joint Comprehensive Plan of Action, the agreement between Iran, the EU, and the five permanent members of the UN Security Council.

The agreement, which limited Iran's ability to enrich nuclear materials to weapons grade for 10 years, was widely seen as one of former president Barack Obama's major foreign policy accomplishments.

While many of Mr Trump's closest advisers — including former secretary of defence James Mattis and former secretary of state Rex Tillerson — counselled him against pulling out of an agreement with which Iran was judged to be in compliance, the president ignored his advisers by refusing to certify Iran's compliance in October 2017. In May 2018 he declared that the US would withdraw from the deal, and by the end of 2018 both Mattis and Tillerson had left government service.

Mr Trump and his administration have since embarked on what he has called a “maximum pressure” campaign akin to the regime of increasingly crippling sanctions which led to his first meeting with North Korean dictator Kim Jong-un, and has routinely spread misinformation about the actions taken by Mr Obama to curb Iran's nuclear ambitions, such as falsely claiming that his predecessor — who he repeatedly accused of being a secret Muslim who was not born in the United States — bribed Iran by settling a long-running legal dispute over a refund for military equipment purchased by the previous government of Iran.

Most of the other permanent UNSC members, however, have opposed the US withdrawal and, led by French president Emmanuel Macron, have endeavoured to keep Iran at the negotiating table even as Tehran has retaliated against US sanctions by restarting uranium enrichment.

Additionally, Mr Trump in April took the unprecedented step of declaring Iran's Islamic Revolutionary Guard Corps — the branch of Iran's military to which Soleimani belonged — a terrorist organisation over the opposition of the Pentagon and CIA. The IRGC Quds Force, which Soleimani led, had been a designated terrorist organisation since 2007.

It was the latter group's designation which figured prominently in a Defence Department statement taking responsibility for the death of Soleimani.

“At the direction of the President, the US military has taken decisive defensive action to protect US personnel abroad by killing Qassem Soleimani, the head of the Iranian Revolutionary Guard Corps-Quds Force, a US-designated Foreign Terrorist Organisation,” Pentagon press secretary Alyssa Farah said in a statement.