In the long term, if/when the world moves to non-fossil energy, then one could make an argument that, broadly speaking, the capability of ME nations to wage war would be commensurate with their non-oil economic power [1].

The question then, how are they going to reach that future equilibrium? Slowly and peacefully, or quickly and violently? Or even quicker with a nuclear Hail Mary pass?

[1] See how they all are scrambling to diversify their economies to not be as reliant on oil?