Bitcoin may have had a bad week, but it will never lack for defenders. On Monday, Mt. Gox, one of the largest trading sites of the digital currency, went offline after it was revealed that it was possibly the target of a $350 to $380 million theft, about six percent of all bitcoin in circulation. Mt. Gox is based in Tokyo, and authorities in both Japan and the U.S. are looking into the security breach, which went unnoticed by Mt. Gox for years. As is Bitcoin itself. Sen. Joe Manchin has already called on federal regulators to ban bitcoin.