Van Buren realized that accommodating slavery expansionists in the South would open the Northern Democrats to charges of appeasement to the Slave power from the strongly anti-annexation Northern Whigs and some Democrats. He crafted an emphatically anti-Texas position that temporized with expansionist southern Democrats, laying out a highly conditional scenario that delayed Texas annexation indefinitely. In the Hammett Letter, published April 27, 1844 (penned April 20), he counseled his party to reject Texas under a Tyler administration. Furthermore, annexation of Texas as a territory would proceed, tentatively, under a Van Buren administration, only when the American public had been consulted on the matter and Mexico's cooperation had been pursued to avoid an unnecessary war. A military option might be advanced if a groundswell of popular support arose for Texas, certified with a congressional mandate. In these respects, Martin Van Buren differed from Henry Clay, who would never tolerate annexation without Mexico's assent.