The term ‘Manifest destiny’ was coined on the occasion of the annexation of Texas (1845). While never official policy, President Polk certainly scented the opportunity to expand from Texas to the Pacific, at the expense of a newly independent Mexican state enfeebled by Comanche and Apache wars. The pretext was a dispute over territory on the Texas-Mexico border along the Rio Grande, to which America made (dubious) claim. An American force was sent to occupy the territory (‘to provoke a fight’ according to Ulysses S. Grant, who was serving there under General Taylor). The Mexicans took the bait, attacking a reconnaissance party: eleven were killed, American blood had been spilt and the war was on. In quick succession, General Taylor’s deployment of ‘flying artillery’ drawn by horsemen secured victory at Palo Alto then Resaca de Palma. Demoralized, the Mexican General Arista withdrew his forces behind (America’s version of) the border.
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