In 2005, the heads of the [[United States]], [[Canada]] and [[Mexico]] met in Waco, [[Texas]] and agreed on a Security and Prosperity Partnership of North America (SPP), which could serve as a stepping stone towards a union.<ref>http://www.spp.gov/</ref> | In 2005, the heads of the [[United States]], [[Canada]] and [[Mexico]] met in Waco, [[Texas]] and agreed on a Security and Prosperity Partnership of North America (SPP), which could serve as a stepping stone towards a union.<ref>http://www.spp.gov/</ref> |