The assassination of a Hamas leader in Tehran humiliated Iran’s leaders, dashed hopes of a ceasefire and left the heavily armed nations of the Middle East moving inexorably closer to an all-out war they all claim not to want

If Iran’s newly elected president, Masoud Pezeshkian, was hoping for a honeymoon period after his inauguration last week, he must be sadly disappointed. Less than 12 hours after Pezeshkian was sworn in, an explosion, reportedly caused by a remotely controlled bomb, shook an Islamic Revolutionary Guard Corps (IRGC) compound in central Tehran. The target: Ismail Haniyeh, Hamas’s political leader, an honoured guest at the inauguration, and one of the Middle East’s most wanted. The bomb under the bed killed Haniyeh instantly. Honeymoon over.

Pezeshkian was the surprise winner of last month’s presidential election. Edging out a conservative hardliner favoured by Ayatollah Ali Khamenei, Iran’s supreme leader, he promised to repair tattered ties with the US and Europe. Many hoped his victory would herald a more open, more progressive era and defuse social tensions, especially over the enforced wearing of the hijab, which triggered huge unrest under his predecessor, Ebrahim Raisi.