It's about the money. That's why big oil has always been a target, it has been the most profitable enterprise in America since Rockefeller formed Standard Oil.
News flash: they also didn't target big tobacco because cigarettes are bad for you (that was merely the excuse they needed), or to pay for healthcare bills. They targeted them to steal / fleece a golden goose, and then divert the stolen money to other projects. Which is exactly what they did.