The very idea of Manifest Destiny
encouraged men and women to dream about boundless opportunity,
supporters said. Senator James Semple (D, Illinois), in debate in the
House over Oregon, noted that in 1843, as many as 1,500 settlers
traveled to Oregon "to reclaim this vast wilderness, and to unite, by
civilization and human intercourse, the shores of the Pacific with the
great West of the Union." Indeed, proponents pointed out, Manifest Destiny inspired pioneers to transform plains and fertile valleys into farms and small towns, helping to build up the nation.
The government not only had a divine right to expand its influence,
supporters said, it also had a duty to incorporate territories to
protect those American citizens who had settled there. Semple asserted
that such expansion expressed the will of the nation to expand. "It is
impossible for [the government] to overlook the expression of public
opinion on this point, so emphatically and universally pronounced. How
was it to act? Was it to allow Great Britain to exercise jurisdiction
over its citizens?" he asked.
Whatever their reasons for seeking expansion, proponents of Manifest Destiny
defended the government's right to acquire new territories, even though
the Constitution did not specifically give it the authority to do so.
Supporters were sometimes labeled as "loose constructionists," because
they interpreted the Constitution "loosely" or broadly enough to say
that, under it, land acquisition was an implied power of the federal
Overall, for supporters of Manifest Destiny,
all factors indicated that the U.S. should push westward. Buchanan
perhaps best summed up the national mood regarding expansion when he
stated: "Prevent the American people from crossing the Rocky Mountains?
You might as well command Niagara not to flow. We must fulfill our destiny."
Critics of Manifest Destiny
rejected the idea that it was God's will or even a good thing for the
country to expand when it resulted in warfare and the subjugation and
mistreatment of native peoples. Expansionists used the concept to
justify their cruel treatment of those peoples, critics asserted. Manifest Destiny, with its talk of the need to "civilize" the "savages" who occupied the west, was also blatantly racist, they asserted.
Unitarian minister William Ellery Channing, in a letter written to
former Senator Henry Clay (Whig, Kentucky) about the annexation of
Texas, described the impact of Manifest Destiny:
Indians have melted before the white man, and the mixed, degraded race
of Mexico must melt before the Anglo-Saxon. Away with this vile
sophistry! There is no necessity for crime. There is no fate to justify
rapacious nations, any more than to justify gamblers and robbers, in
plunder ... We talk of accomplishing our destiny. So did the late conqueror of Europe [Napoleon Bonaparte]; and destiny consigned him to a lonely rock in the ocean, the prey of ambition which destroyed no peace but his own.
Critics grew particularly incensed when the concept was used to justify
wars of expansion. God would not destine a nation to kill and subjugate
people, they argued. If the "war be right then Christianity is wrong, a
falsehood, a lie," Congregationalist minister Theodore Parker asserted
in opposition to the war with Mexico.
Many in particular portrayed the Mexican-American War as a land grab,
aimed at the conquest of a vulnerable neighbor with little ability to
defend itself. Critics argued that Manifest Destiny
was used to justify imperialism, and that the U.S. would never have
tolerated being treated the way it was treating other countries.
Senator Thomas Corwin (Whig, Ohio) was a particularly strong critic of
the war with Mexico. According to him: [See Senator Corwin Criticizes Concept of 'Manifest Destiny' (Excerpts) (primary document)]
one come and demanded Bunker Hill of the people of Massachusetts, had
England's lion ever showed himself there, is there a man over 13 and
under 90 who would not have been ready to meet him; is there a river on
this continent that would not have run red with blood; is there a field
b