The reasons for the build are strait forward. Energy security and options. There is a war going on. Everytime the FED raises rates to fight inflation OPEC cuts production. Russia and China have officially unified and Broke the US dollars hegemony internationally with 16 more nations applying to be part of BRICS.
The last 50 years of energy security and power of USD is because of the petro dollar. OPEC has made their stand clear that the deal is over.
The US could be energy independent, but it is not. We still can drain more of the SPR, but its only a matter of time. Pump gas will continue to be volitile and soaring price cycles or limited availability long before LPG is effected...and it stores so easy to keep it topped off at 1 years worth of fuel at all times