not maneuver aggressively enough to prevent Lee from crossing the Potomac to safety on the night of July 13–14. Background Lee's plans Shortly after Lee's Army of Northern Virginia defeated Hooker's Army of the Potomac during the Chancellorsville Campaign (April 30 – May 6, 1863), Lee decided upon a second invasion of the North. Such a move would upset Union plans for the summer campaigning season, give Lee the ability to maneuver his army away from its defensive positions behind the Rappahannock River, and allow the Confederates to live off the bounty of the rich northern farms while giving war-ravaged Virginia a much needed break. Lee's army could also threaten Philadelphia, Baltimore, and Washington, and encourage the growing peace movement in the North. Lee had numerous misunderstandings that shaped his strategy. Lee misread Northern opinion by his reliance on anti-war Copperhead newspapers for northern public opinion. Reading them, he assumed the Yankees must be just as war weary as southerners, and did not appreciate the determination of the Lincoln Administration. Lee did know he was seriously short of supplies for his own army, so he planned the campaign primarily as a full-scale raid that would seize supplies. He wrote: If we can baffle them [Yankees] in their various designs this year & our people are true to our cause...our success will be certain.... [and] next year there will be a great change in public opinion at the North. The Republicans will be destroyed [in the 1864 presidential election] & I think the friends of peace will become so strong as that the next administration will go in on that basis. We have only therefore to resist manfully. Lee was overconfident of the morale and equipment of his "invincible" veterans; he fantasized about a definitive war-winning triumph: [The Yankees will be] broken down with hunger and hard marching, strung out on a long line and much demoralized when they come into Pennsylvania. I shall throw an overwhelming force on their advance, crush it, follow up the success, drive one corps back on another, and by successive repulses and surprises, before they can concentrate, create a panic and virtually destroy the army. [Then] the war will be over and we shall achieve the recognition of our independence. The Confederate government had a different strategy. It wanted Lee to reduce Union pressure threatening their garrison at Vicksburg, Mississippi, but he rejected its suggestions