The shamefulfeelingsthat one or a few bad apples bring to their respective race, group or even place.
Cholos like Nortenos, Surenos are an embarrassment to their Mexican race who strive for a better future. Racist whites, white supremacists like the KKK German Nazis are an embarrassment to all Germans. Asian gangsters have become an embarrassment to their own kind who are hardworking people.
You have to wonder whether it's more of an embarrassment for Trump or Biden (or both) that Trump hasn't given up on himself, if any of it matters enough to wonder about it.
Biden says it's an embarrassment (for Trump and America is implied) that Trump hasn't quit the race but puts his face down as he's saying it. How can anybody respect either one of them?