Why did Riyadh join US strikes on Tehran's allies in Iraq?

Following months of military restraint, Saudi Arabia on Wednesday joined the US in striking Iran-backed militias in Iraq, marking Riyadh's first direct military involvement alongside Washington since the Iran war erupted in late February. US Central Command (CENTCOM) said the strikes targeted logistics hubs and weapons depots operated by militias acting under the direction of Iran's Islamic Revolutionary Guard Corps (IRGC). Saudi officials described the operation as an act of self-defence, accusing Iran-backed groups in Iraq of launching drone attacks against the kingdom's energy infrastructure earlier this week. The Hashed al-Shaabi alliance, also known as the Popular Mobilisation Forces, an umbrella organisation that includes many of Iraq's pro-Iranian Shia militias, said around 20 of its fighters had been killed. The strikes represent a marked departure from Saudi Arabia's approach over recent months. "It's a very big shift, it looks like the Saudis are getting more openly militarily involved [...] after a few months of very severe restraint," said Toby Matthiesen, senior lecturer in Global Islam at the University of Bristol. From restraint to retaliation Since the US-Israeli of...