Who is credited with coining the term "Manifest Destiny"?

The term "Manifest Destiny" is credited to John O'Sullivan, a journalist and editor. He first used the phrase in 1845 in the context of the United States' expansionist ambitions, particularly regarding the annexation of Texas. O'Sullivan's writings expressed the philosophy that it was the undeniable fate of the United States to expand across the North American continent, which he believed was sanctioned by divine providence. This concept became a significant justification for westward expansion, influencing both public opinion and government policy during the mid-19th century. O'Sullivan's framing of Manifest Destiny captured the national sentiment of the time, suggesting a moral responsibility to spread democracy and civilization, which resonated with many Americans and became a driving force behind territorial expansion.