Who proposed that the U.S. should declare war on Mexico to retrieve land?

The proposal for the U.S. to declare war on Mexico in order to retrieve land is most closely associated with General William T. Sherman, who was a prominent military figure during the time of the American Civil War and the Mexican-American War. Sherman believed in the expansion of U.S. territory and, as part of the military leadership, supported military action that aligned with this goal. His advocacy for territorial expansion was influenced by the idea of Manifest Destiny, which was prevalent in the mid-19th century.

In contrast, figures like Teddy Roosevelt and Bill Richardson were not directly associated with land retrieval from Mexico through war; Roosevelt's actions were more aligned with imperialism in the late 19th and early 20th centuries, while Richardson was focused on modern political issues. George Curry, though a historical figure, does not have a well-documented connection to the pro-war sentiment concerning Mexico in the context of land acquisition. Hence, General Sherman stands out as the key figure proposing military action against Mexico for territorial expansion.