Myth: America "lost" it's moral authority.

It makes me snicker when I hear some conservative bray on about American exceptionalism in a world of backwards actions, immoral leaders, and corrupt governments. It makes me shake my head when I hear some liberal run his/her mouth about how America has "lost it's moral authority" in the world.

What moral authority did it ever have to begin with?

I think displaced Native Americans, past and present, might have a say on this.
I think Black slaves, then "freed" to be segregated, might have something to chime in with.
I think subjugated women might have an opinion.
I think Jews stopped at a Florida harbor and sent back to Germany by FDR might have something to say.
I think Mexican-American Tejanos in grossly underfunded schools for decades and decades might ask where this authority was,
I think the hoards of exploited European and Asian immigrants might want to see this morally sound benchmark.

Perhaps those in 1950's Iran who watched their elected leader be overthrown with the help of a CIA coup might have a say in this?
How about those who watched American interventionism in Latin America for decades?

Or can we cut these people out of the discussion on moral high ground and exceptionalism?