The signing of a 20-year agreement for U.S. gas producer Caturus’s Commonwealth liquefied natural gas (LNG) division to supply one million tonnes per ‌annum of LNG to Saudi Arabia’s Aramco is enormously significant both inside and outside the energy market. At a time when LNG has become the world’s most flexible instrument of energy statecraft, the decision by Aramco to lock in U.S. supply for two decades may speak to a deeper geopolitical recalibration underway in Riyadh. For Washington, meanwhile, the agreement offers a…