The title of this Agora and the first question it poses both ask whether treaties are in decline. With respect to multilateral treaties to which the United States is a party, the answer is a clear yes.
According to the U.S. State Department’s Treaties in Force database, the United States became a party to a record number of 105 multilateral treaties between 1990 and 1999. As set forth in Graph A below, during the period 2000–2009, the number of multilateral treaties the United States joined dropped to just 62, the lowest number since the 1960s. The preliminary data from the first part of this decade beginning in 2010 suggests that this downward trend continues, but it is still too early in the decade to draw any definitive conclusions.