This is expected when you withdraw from the Iran nuclear deal. Maximum pressure has been met with maximum resistance from Iran. The policy by the Orange tyrant has been a spectacular failure. The hardliners in Iran are getting more powerful and more sway in the government. The recent escalations in Saudi Arabia, Persian Gulf and now this. This is all a broader plan by Iran to flex it’s muscles that they will not bend under US maximum pressure.
I expect Kataib Hezbollah and other shia militias to launch further attacks. This will be a flashpoint in 2020. Trump will face a tough choice because of his stupid Mideast policy. Withdraw from Iraq or further escalation with Iranian proxies which could spiral into a wider regional war.