The modern world needs a few things: Gas, food, and functioning economies. Russia's economy is almost entirely dependent on oil and natural gas exports. It provides more than a third of Europe's oil and natural gas. And about 80 percent of that comes through pipelines in Ukraine. 

Russia is Europe's biggest gas supplier; daily flows of that commodity are worth almost $100 million a day. The largest consumer of that gas? Germany. But what about in the U.S.? Domestically, we import only a little gas and oil from Russia, about 5 percent. But even small energy disruptions across the globe could make our fuel prices rise.

Follow Adriene Hill at @adrienehill