The crisis caused by the US-Israel war on Iran has affected the member states of the Gulf Cooperation Council (GCC) at different levels.Oman has barely felt any shock as its ports and terminals continue operating as usual. Saudi Arabia and the United Arab Emirates have been able to reroute some oil exports through terminals in Yanbu and Fujairah, respectively, to bypass the Strait of Hormuz. Kuwait, Bahrain and Qatar, on the other hand, have been practically cut off from the global market and are facing the prospect of economic contraction.Under these circumstances, the GCC states more than ever need to demonstrate unity and address the crisis through collective action. The issue of solidarity is not about showing benevolence to neighbours. It is about setting up mechanisms now that can diminish the consequences and value of any future threat of closure. It is about the survival of the whole idea of GCC unity and the leverage it has on the global scene.Collective action, common interestEven if some sort of agreement is reached between the warring sides today, the GCC will continue to suffer under the shadow of the nearly three-month closure. States face the risk of losing clients due to the risk of not fulfilling their obligations or be …