According to US historians, the philosophy behind the US was always about diversity, equity and inclusion, especially the postbellum US, when in Reformation the all men are created equal language was clarified as universalist.

Even before then, the concepts from the Enlightenment challenged the stratified society structure of the feudal monarchies. There was a general belief that slavery was a moral failing. However, many of the framers were slaveholders themselves, and even then the plantations were leveraging their wealth and power and lobbying to preserve the racist hierarchy.

Sadly, consolidation of wealth and political power was an impetus even then, and when we abolished slavery, the landowners did everything in their power to entrap their freed slaves into their former roles. When sharecropping and debt servitude failed, capitalists invoked the truck system, child labor, prison labor, immigrant labor (notably the Chinese, later, Irish and Italians, then the various Latins), and then moving factories to undeveloped countries that had weaker labor laws and bribable officials. Our current system of wage bondage, debt bondage and the suppression of labor has shown that common Americans have never really escaped serfdom. Only it’s to corporations rather than unilateral liege lords.

This is to say, the current playbook is the same one it always was, just far more extreme and reactionary and backed by more wealth than ever before. (Rockefellers and Vanderbilts were never as rich as the top millionth of a percent we have today.)

ETA: And all that is to say that when Trump and the far right propaganda machine campaigned against DEI, it was openly abandoning the fundamental pretexts of the great experiment that is the United States of America. Trump wants to be king, but then so do all the billionaires that financed his campaign.