One indication of moral progress in the United States would be the replacement of Thanksgiving Day and its self-indulgent family feasting with a National Day of Atonement accompanied by a self-reflective collective fasting.
In fact, indigenous people have offered such a model; since 1970 they have marked the fourth Thursday of November as a Day of Mourning in a spiritual/political ceremony on Coles Hill overlooking Plymouth Rock, Massachusetts, one of the early sites of the European invasion of the Americas.
Not only is the thought of such a change in this white-supremacist holiday impossible to imagine, but the very mention of the idea sends most Americans into apoplectic fits -- which speaks volumes about our historical hypocrisy and its relation to the contemporary politics of empire in the United States.