Meanwhile, there was Lincoln, who—perhaps more than any other President—saw the full potentialities of a President’s wartime powers and used them up to the hilt. What about him? What came of his essay in understanding and exercising the enormous authority which the Constitution gives to a chief executive in time of war?

A great deal came of it, including a complete transformation of American society and a revolutionary change in the American scheme of things. Lincoln accepted the challenge of secession in 1861 as something revolutionary, and he did not hesitate to use revolutionary means to meet it. His war powers, as he saw them, were all but unlimited; in effect, he believed that as commander in chief he could do just about anything that needed to be done to win the war, and most of these things he unhesitatingly did. America has never been the same since.

Allan Nevins looks into all of this in the sixth volume of his monumental examination of the causes, development, outcome, and effect of the Civil War, entitled The War for the Union: War Becomes Revolution, 1862–1863 . He begins his story early in 1862, when the Federal cause seemed to be winning on all fronts, takes it through the disasters which were inflicted in the spring and summer of that year, and goes on to the beginning of the summer of 1863, when the Union cause was on the verge of winning the enormous victories of Vicksburg and Gettysburg; and he is concerned not so much with showing how and why an apparent victory turned to defeat and then became victory again, as with tracing what happened to the American nation in the process.

What happened to the nation, as Mr. Nevins sees it, was that in effect it was born anew. It became a different nation. It had been loose, amorphous, a sprawling agglomeration of people and resources which, amoeba-like, had no real central nervous system and no real sense of direction. It became hard, compact, organized, a modern America swinging enthusiastically into the industrial revolution, compressing into a few years a development which otherwise might have taken decades, or for that matter might have come out quite differently; and this happened, mostly, because the President with intense singleness of purpose marshaled all of the country’s powers for victory in war.

To do all of this, Mr. Nevins believes, Lincoln had to handle a political-party revolution, an economic revolution, and a social revolution—and, possibly, an intellectual revolution as well. His armies not only had to win victories in the field; they had to be organized, equipped, transported, and supported in such a way that the victories would be possible, and to do all of this changed the nation. The American businessmen had to learn—and the war soon taught them—that they could “create a new economic world as the Revolutionary generation had created a new political world.” The ordinary