I think Americans have been unified at times. E.g. in the first two years of World War Two. Polls repeatedly demonstrated Americans from many walks of life were uniformly against intervening in the new world war.

While I'm not familiar with the pollsters' methodology, it's hard to believe that black people, Latinos, Muslims or LGBTQ folk would have felt any differently.

Of course people were aware, & appalled, by the NDSAP's brutality & overt racism & anti-semitism. But the US had intervened in the Great War, & it got us what, aside from 90K dead & countless physical & mental injuries? If Europeans couldn't learn to get along & play nice, how it was it the US's responsibility.

There's a conversation to be had over the actual necessity of World War Two, the "good war", but this is not the place. So, assuming the Greatest Generation was correct in holding that our intervention did turn out to be necessary, I still think of the American public's position in the years between Poland & Pearl Harbor as an example of being wrong for all the right reasons.

But certainly we were unified then.