Calhoun gained significant credibility when his former nemesis, ex-President Andrew Jackson, publicly announced his support for immediate Texas annexation in May 1844. Jackson had facilitated Tyler's Texas negotiations in February 1844 by reassuring President of the Texas Republic Sam Houston that the US Senate ratification of the Tyler treaty was likely. As the Senate debated the Tyler treaty, Jackson declared that the popular support among Texans for annexation should be respected, and any delay would result in a British dominated Texas Republic that would promote slave emancipation and pose a foreign military threat to the southwest United States.