That was exactly what he was trying to do, that is fight defensively at the The Battle of Cashtown. A.P.Hill precipitated the larger battle at Gettysburg, more or less against orders. Then Early misinterpreted his orders and neglected to to take and hold the ridge for the Confederates, allowing Meade, who really didn't want to fight at Gettysburg either, to do so.
It was a mix-up based on faulty, or rather primitive, intelligence all around. How, for example, did Meade's staff miss the importance of Little Round Top until it was almost too late?
Let's face it, you unrepentant rebels out there, Marse Robert was damn good on defense and counter-punching on home ground in VA, he was less than stellar on the invasion thing and a more or less complete dunderhead logistically. The Confederates, who had admittedly less to work with than the Union in materièl, were nonetheless very poor at Quartermastering what they did have, failing even to feed and clothe their troops at a basic level. No excuse for it.
What the Civil War really proved militarily is that you cannot fight a massive war without centralized command and control. In other words, a strong centralized Federal government that tells the states what to do. The Confederacy, actually the second confederacy in our history, had less power over their states.
Wars, whether necessary like 1812, or unnecessary, like 1898 and WWI, lead inexorably to centralized Federal power and away from the original Constitution and the rights of sovereign states. We are still organized for war, not for peace nor for government as envisioned by our Founders.
Comment of the week IMHO.
Agreed, except I'd give you an argument on 1812 being "necessary."
It is also difficult to make out a case for the Mexican War being "necessary."