He had then denied that the idea was the invention of any one man, and scouted the notion that on this doctrine there could be any difference of opinion among Whigs.

On March 7 he announced that he would not have the proviso attached to the territorial bills, and should oppose any effort in that direction.

The reasons he gave for this apparent change were, that nature had forbidden slavery in the newly-conquered regions, and that the proviso, under such circumstances, would be a useless taunt and wanton insult to the South.

The famous sentence in which he said that he "would not take pains uselessly to reaffirm an ordinance of nature, nor to reenact the will of God," was nothing but specious and brilliant rhetoric.
It was perfectly easy to employ slaves in California, if the people had not prohibited it, and in New Mexico as well, even if there were no cotton nor sugar nor rice plantations in either, and but little arable land in the latter.

There was a classic form of slave-labor possible in those countries.