Power

As everyone learned in school (or from watching Ellen, the President of the United States is one of the most powerful people in all of humanity—and a really slick dancer. He (or she, depending on when you're reading this) is the CEO of the Executive Branch of the United States government. He or she is the Commander in Chief of the U.S. Armed Forces, and also the Leader of the Free World™.

And that person will likely pick up the phone right when you call.

The president isn't the only one who'll pick up that call, either. The fortunes and futures of entire countries (and often the families that rule them) hinge on the import or export of fossil fuels. The United States uses about half of the oil that it drills, selling most of the rest to countries that want it. 

We also, for some ridiculous reason, buy oil too, even from places with questionable relationships with human rights, like Saudi Arabia and Nigeria.

 
One twist and the economy goes kaput. (Source)

Since you'll be in direct control of extractors, pipelines, oil fields, and other major sectors of this industry, a lot of very powerful people will have to deal with and appease you. Blocking the flow of oil will wreak havoc just about anywhere, and you have the power to take away that resource on a whim. It's probably not the best idea, buy hey, you can do it.