Why Calhoun opposed the Conquest of Mexico

American politicians are fond of talking about "who we are", with some saying that we are all egalitarians and some saying we are all racists. Apparently there is a disagreement that can be informed by historical documents.

US Senator John C. Calhoun wrote in 1848 against the conquest of Mexico:

RESOLVED, That to conquer Mexico and to hold it, either as a province or to incorporate it into the Union, would be inconsistent with the avowed object for which the war has been prosecuted; a departure from the settled policy of the Government; in conflict with its character and genius; and in the end subversive of our free and popular institutions. ...

We have conquered many of the neighboring tribes of Indians, but we have never thought of holding them in subjection — never of incorporating them into our Union. They have either been left as an independent people amongst us, or been driven into the forests.

I know further, sir, that we have never dreamt of incorporating into our Union any but the Caucasian race — the free white race. To incorporate Mexico, would be the very first instance of the kind of incorporating an Indian race; for more than half of the Mexicans are Indians, and the other is composed chiefly of mixed tribes. I protest against such a union as that! Ours, sir, is the Government of a white race. The greatest misfortunes of Spanish America are to be traced to the fatal error of placing these colored races on an equality with the white race. That error destroyed the social arrangement which formed the basis of society. ...

Sir, it is a remarkable fact, that in the whole history of man, as far as my knowledge extends, there is no instance whatever of any civilized colored races being found equal to the establishment of free popular government, although by far the largest portion of the human family is composed of these races. And even in the savage state we scarcely find them anywhere with such government, except it be our noble savages — for noble I will call them. They, for the most part, had free institutions, but they are easily sustained among a savage people. Are we to overlook this fact? Are we to associate with ourselves as equals, companions, and fellow-citizens, the Indians and mixed race of Mexico? Sir, I should consider such a thing as fatal to our institutions.

It is debatable whether this view should be considered "white supremacist". He regarded whites as more civilized than other races, but he has no desire to rule over other races. As he just wants to stay separate from other races and nations, I would call this "white nationalist" or "white separatist", but some people call it "white supremacist".

I wonder what Calhoun would say today about the Mexican conquest of California.

The NY Times regularly has article about how only white supremacists support President Trump, and that whites are desperately hanging on to power in the face of their "inevitable ... demographic displacement" by non-white. There is another such article today.

The NY Times is as anti-white and Calhoun was pro-white.

The NY Times also has an article today complaining that Pres. Trump refuses to sign on to international Jewish attempts to re-engineer the internet to block certain points of view. In particular, they want to allow comments favoring the demographic displacement of Whites, while blocking criticisms of it.