When President Obama opened the coastline to offshore oil drilling, nearly every aspect of the plan came under heated debate. The only thing everyone agrees on, it seems, is the need to reduce our dependence on foreign oil. Statements from the Environmental Protection Agency to automakers to T. Boone Pickens to Obama himself, whether supporting or condemning offshore drilling, all cite the dangers of relying on foreign energy. It's not hard to see why. Shipping oil from halfway around the world is environmentally costly, economically inefficient, and lands us in bed with some of the world's least democratic regimes. But our ties to these states might not be categorically terrible things for us, as they're often assumed to be. Hidden unexamined among the many downsides of our dependence on foreign oil is an upside: It gives us leverage over the countries that sell us oil.

The top ten oil exporters to the U.S., which account for half of all U.S. consumption, read like a State Department tourism warning list: Saudi Arabia, Venezuela, Nigeria, Iraq, Angola, Russia, Colombia, and Brazil. (To be fair, Canada has long been our number one oil source, and Mexico alternates with Saudi Arabia for the number two spot.) But keep in mind that most of these countries need our money a lot more then we need their oil. If Saudi Arabia and the U.S. suddenly ended our trade tomorrow, for example, the U.S. and global economies would not suffer nearly as much as Saudi Arabia's. The Saudis understand this and so want to keep U.S. and Saudi interests aligned.

As a result, buying Saudi oil gets us a lot more than just energy. It gets us a dedicated ally that wields unparalleled influence in a part of the world where we desperately need it: the Middle East. The Saudi royal family has put their wily intelligence service at our disposal and allowed sprawling U.S. military bases onto their soil. In 1992, the Saudis even exiled one of their own on America's behalf: A prominent, wealthy, and popular humanitarian and freedom fighter named Osama bin Laden. Saudi royalty risked a violent backlash by expelling bin Laden to Sudan, but U.S. officials had demanded his ouster. That's no small favor. It would be almost as if the United States deported Google CEO Eric Schmidt to Honduras at the request of angry Chinese officials. The Saudis came to our aid again in 1996 when they convinced the Sudanese regime to themselves deport bin Laden.

Bin Laden's anti-American terrorism did not begin until he fled to Afghanistan, where the United States then had little influence. In the decade since, he has moved between there and Pakistan, two countries with which the U.S. has no meaningful economic ties save foreign aid. Unlike with Saudi Arabia, our pleas to those governments to help us rout bin Laden went largely ignored.

If our oil-greased relationships with other top producing states are half as close as the U.S.-Saudi partnership, it will give us much-needed leverage over some of this century's biggest emerging threats. In Nigeria, we can pressure the government to peacefully contain the state's alarming increase in terrorism. For Iraq, the economic ties with America would be an important counterbalance to Iran's religious and political influence. As for Venezuela, no matter how antagonistic President Hugo Chavez gets, he would be a lot worse if we didn't take close to a million barrels off his hands every day.

The point isn't that dependence on foreign oil is a good thing. The political, economic, and environmental costs are severe, unsustainable, and require long-term alternatives. But as we seek to reduce our dependence on foreign oil, it's important to remember that our influence with certain key states will reduce as well.

Image: Oil workers maintain a drill in Kuwait, circa 1950. David C. Foster, Flickr creative commons.