Manifest Destiny and the Mexican-American War



O'Sullivan, Polk, and much of the Public, wholeheartedly supported the war, believing in Manifest Destiny and westward expansion.

"As war exists, and, notwithstanding all our efforts to avoid it, exists by the act of Mexico herself, we are called upon by every consideration of duty and patriotism to vindicate... the rights, and the interests of our country..."                   
--Pres. James K. Polk, essentially saying that Mexico is for him because they
"attacked" first (PBS)

President Polk

-Polk: ardent supporter of expansionist and imperial efforts, main consistencies of his Presidency.

-His message on war with Mexico included pro-expansionist sentiments.

-Justified war with Manifest Destiny; explicitly also with Mexicans "attacked" American troops first in Thornton Affair


-O'Sullivan championed war efforts, believing it to be in America's best interest.

-Also justified war with Manifest Destiny and said that America did nothing wrong.

-"No instance of aggrandizement or lust for territory has stained our [American] annals"

The Public

-Public opinion at beginning of war largely patriotic, most of the people supported the war.

-Press coverage and nationalistic pride cause general public to support American troops.

-"romantic spirit and sense of adventure" (Herring 203).

"Congress's action unleashed enthusiastic public demonstrations...20,000 Philadelphians gathered to voice their support of the war..."
(Johanssen To the Halls 8)

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