Widely considered a settled issue during the late 20th century, the terrorist attacks of September 11, 2001 demonstrated the potential for a decapitation strike that would kill or incapacitate multiple individuals in the presidential line of succession in addition to many members of Congress and the federal judiciary. In the years immediately following the attacks, numerous wide-ranging discussions were started, in Congress, among academics and within the public policy community about continuity of government concerns including the existing constitutional and statutory provisions governing presidential succession. These discussions remain ongoing. One effort put forward by the Continuity of Government Commission, a nonpartisan think tank, produced three reports (2003, 2009 and 2011), the second of which focused on the implicit ambiguities and limitations in the current succession act, and contained recommendations for amending the laws for succession to the presidency.