Of course I read - but do you think? Would you feeeeeeeeeeel better if Lincoln had immediately set out to crush the treasonous rebellion instead of first attempting peaceful solutions?
As I have indicated previously, I remain quite ambivalent about the matter of the Civil War; neither side was entirely pure, in my opinion.
But I would be careful about attaching the adjective, "treasonous," to the South's insurrection. The word tends to carry very negative implications; but what is called "treason" (when the insurrection is unsuccessful) is usually termed "patriotism" whenever it is successful. (For instance, just compare the insurrection known, in America, as the American Revolution, with the one known as the Civil War.)
Oh, and successful insurrections are usually known as revolutions (e.g. the American Revolution; the French Revolution; the Russian Revolution; etc.), whereas unsucccessful ones are known as rebellions (e.g. Shay's Rebellion; the Whiskey Rebellion; etc.).
In other words, language that may appear, on the surface, to be quite neutral, is sometimes anything but that...