The 11th President, James Polk, presided over the Mexican-American War, which ended with the US annexing most of the southwest. He also threatened to go to war with Britain (who still hadn't learned their lesson) over who owned the Oregon Country, which included Washington State. When he ran for office, he vowed to serve only one turn, and did not run for re-election. Perhaps most importantly, he was the President with the most bodacious mullet.
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