" The Reverent Theodore Parker, Unitarian minister in Boston, combined eloquent criticism of the war with contempt for the Mexican people, whom he called 'a wretched people; wretched in their origin, history, and character,' who must eventually give way as the Indians did. Yes, the United States should expand...by 'the steady advance of a superior race, with superior ideas and a better civilization...by being better than Mexico, wiser, humaner, more free and manly'.
...The racism for Parker was widespread. Congressmen Delano of Ohio...opposed the war because he was afraid of Americans mingling with an inferior people who 'embrace all shades of color....a sad compound of Spanish, English, Indian, and negro bloods...and resulting, it is said, in the production of a slothful, ignorant race of beings'. "

― Howard Zinn , A People's History of the United States