The Pentagon conducted its first war game where the weapons don't go BANG, but BUST -- as in economic bust. According to Politico, one source who attended explains why the miliatry is interested in economic warfare: "'Why would the military care about global capital flows at all? asked another person who was there. "Because as the global financial crisis plays out, there could be real world consequences, including failed states. We've already seen riots in the United Kingdom and the Balkans.'" In the article, Paul Bracken of Yale says, "The purpose of the game is not really to predict the future, but to discover the issues you need to be thinking about."
Though it may be tempting to consider economic warfare through Napolean's axiom ("an army fights on its stomach"), where the inability to pay for a war causes an enemy to capitulate, I'd think the application here given the connectedness of markets would be defeating a country's will to fight before a shot is fired. The worse an adversary believes their future will be, the better. For example, if China one day said "we're taking Taiwan or dumping every dollar we have," well, then, it would certainly be food for thought. Same thing with the US instituting trade/financial flow blockades against a highly connected country.
Sorry for the doom & gloom. Here's Christopher Walken's "Weapon of Choice" video to cheer you up.