The national idea and interest, that is, was not merely disarmed and ignored, as it had been by Jefferson.

It was mutilated and distorted in obedience to an erroneous democratic theory; and its friends, the Whigs, deluded themselves with the belief that in draining the national idea of its vitality they were prolonging its life.

But if its life was saved, its safety was chiefly due to its ostensible enemies.

While the Whigs were less national in feeling and purpose than their ideas demanded, the Democrats were more national than they knew.

From 1830 to 1850 American nationality was being attenuated as a conscious idea, but the great unconscious forces of American life were working powerfully and decisively in its favor.
Most assuredly the failure of the Whigs is susceptible of abundant explanation.