Briefly explain ONE historical event of development in the period 1830-1869 hat is not explicitly mentioned in the excerpts could be used to support Wilentz's interpretation.

"The Manifest Destiny impulse fed off a mixture of crassness, truculence (hostility), and high idealism. Without question, there were those who proclaimed America's providential mission to expand as a eulogistic (honorary) cover for speculation in land and paper. But those were hardly the motives of John O'Sullivan, the writer who coined the term... For O'Sullivan and his allies, the expansionist imperative was essentially democratic... in a supercharged moral sense, stressing America's duties to spread democratic values and institutions to a world still dominated by monarchs and deformed superstitions." --Sean Wilentz, The Rise of American Democracy, 2005.