American politicians love to talk about energy security. Republicans love it. Democrats love it. Mitt Romney. Barack Obama. Buddy Roemer probably even brought it up at some point. Everyone is for energy security. 

But what, exactly, is energy security? 

The non-partisan Congressional Budget Office (CBO) took a stab at answering that question in a report this month that included this helpful info-graphic, which I've included below. Here's the rundown: Often times, when politicians and the media discuss energy security, they're talking about reducing imports -- about America's ability to produce all of our power and fuel needs either at home, or in nearby, friendly nations like Canada. In other words, what they're really talking about is "energy independence."

The CBO believes that's the wrong way to frame the issue. Energy security, it says, is really about making sure the cost of power and fuel stays cheap, no matter what's going on in the world around us. The only way to ensure that is by diversifying the resources we use. Consider electricity prices, which have stayed relatively stable for decades. Why? Because our utilities use all sorts energy sources, including coal, natural gas, hydro-electric, and nuclear. If one of those resources is disrupted, we can move to another. Now compare that with gasoline, which has see-sawed violently over the last several years along with the global price of oil.

But wouldn't drilling more of our own crude protect us from those swings? No, it wouldn't. As the CBO notes, even countries that export oil still have to pay prices set on the world market for what they use at home. You don't get any special discounts for drilling it up locally. 

The moral? Drilling for more oil might increase our energy "independence." But it won't make us more secure.