What was the Occasion?

[L Verge]

I recently purchased a new novel entitled The Lincoln Myth. It seems to be like National Treasure: Book of Secrets in a way. The mystery begins during the Lincoln administration, but most of the action is in modern times.

However, there is a quote in the front of the book from Mr. Lincoln dated January 12, 1848. I would like to know what the occasion was that prompted this statement. It is definitely a 360-degree turn from the Lincoln policies of 1860.

"Any people anywhere, being inclined and having the power, have the right to rise up and shake off the existing government, and form a new one that suits them better. That is a most valuable, a most sacred right -- a right, which we hope and believe, is to liberate the world. Nor is this right confined to cases in which the whole people of an existing government may choose to exercise it. Any portion of such people, that can, may revolutionize and make their own of so much of the territory as they inhabit."

It seems very Jeffersonian, but certainly smacks of the right of secession. It also seems to support Stephen Douglas's later platform of let the people of a territory decide the issue of slavery. What gives? Is this just another example of Mr. Lincoln swaying in the breeze of political expediency?