On April 20, 2010, the Macondo well suffered a blowout, causing the mobile offshore drilling unit "Deepwater Horizon" to explode and eventually sink. Oil flowed from the well into the Gulf of Mexico for 87 days. In the aftermath of this event, the US Government proposed significant regulatory changes related to offshore oil and gas exploration and production. In this paper I consider the likely costs and potential benefits from these new regulations. While both costs and benefits are very large, plausibly running into billions of US Dollars, a strong case can be made in favor of the regulations.