 The Articles of Confederation of 1781 among the 13 American states fighting British rule had established a center too weak for law enforcement, defense and for securing interstate commerce. What has become known as the U.S. Constitutional Convention met May 25–September 17, 1787. It was explicitly restricted to revise the Articles, but ended up recommending more fundamental changes. The proposed constitution prompted widespread debate and arguments addressing the benefits and risks of federalism versus confederal arrangements, leading eventually to the Constitution that took effect in 1789.