Doctorow becomes a Civil War novelist

E.L. Doctorow (Ragtime), a 1970s New Yorker contributor cum historical novelist has the Civil War in mind. His new novel The March, is collecting its first reviews:

Sherman's war-loving subordinate Justin "Kil" Kilpatrick blithely rapes and loots, finding a boy's excitement in bloody exigencies. [...] Doctorow patiently weaves these and several other stories together, while presenting military strategies (e.g., the "vise" formed by Sherman's gradual meeting with Grant's Army) with exemplary clarity. Behind it all stalks the brilliant, conflicted, "volatile" Sherman, to whom Doctorow gives this stunning climactic statement: "our civil war . . . is but a war after a war, a war before a war."
What a nice tickling of our vague antiwar instincts. But I have failed to find this quote. Has it been fabricated for him?

Sherman was not a nihilist. He chose sides during the War of the Rebellion without resorting to dice or the flip of a coin. He believed in killing for a cause, an impossibility for those who think every war is but another war. Consider this thinking -
My aim, then, was to whip the rebels, to humble their pride, to follow them to their inmost recesses, and make them fear and dread us. Fear is the beginning of wisdom.
Not the words of "just another war" speaking. And Civil War buffs, at whom Doctorow's publisher is now making lustful eyes, reject the notion that this was just another war.

But tell me that this is merely a Doctorow novel after a Doctorow novel before a Doctorow novel and I'm with you.

p.s. 8/18/05 - I assume Doctorow has "crafted" this quote in Sherman's voice. Brooks Simpson, co-editor of Sherman's Civil War: Selected Correspondence of William T. Sherman, 1860-1865 has commented on Usenet about this Doctorow quote, "I've never heard such a quote attributed to Sherman."