>Manifest destiny was a widely held belief in the 19th century United States that its settlers were destined to expand across North America.
The average American does not think that America should expand any further throughout the world, nor do they think that America has an irresistible duty to remake the world in its image. The theme of "the special virtues of the American people and their institutions" is only one part of the definition of manifest destiny.
Also, if you've ever read an HN thread on public mass transit, I think there is evidence against the claim that Americans think that all of their institutions are the best in the world.