The manufacture and sale of gasoline and diesel engines would be phased out quickly. Everything would be switched over to Hydrogen.
Look the guys who created the hydrogen fuel cell made a big mistake by putting it in that dumb-ass scooter. Hardly anyone could look past the scooter and see that the engine and fuel cells were the real invention, but if we get behind this thing it can change everything. Put it in cars, trucks, generators that power cities. I don't know if can work in airplanes, but if it can, then put it in them too. It's freekin insane not to.
Then most of the middle east can go back to being useless desert.