Lee was the tactician. He had no grand strategy for winning the war. Sherman was the strategist who had problems managing individual battles.
“Lee was the tactician.”
I disagree.
Knowing the South was greatly outnumbered in terms of both men and materiel, Lee’s strategy was to remain mobile, spread the Union forces and keep them guessing. That worked, especially with Jackson’s brilliant Shenandoah Valley campaign. But Lee also knew that there was no way the South could prevail in a protracted war, so he decided that the only way for the South to win would be to win a decisive battle on Northern soil, and then march toward D.C. and invest the Capital, upon which he believed the North would seek terms and let the Confederacy go on its way. Hence, that is why he invaded southern Pennsylvania, and why he fought at Gettysburg. Remember, the Union had been getting bloodied all over the Eastern Theater, and its hold on the Mississippi Valley was not all that secure.
Lee saw Gettysburg as his best — and probably only — chance to win on terms favorable to the Confederacy, and historians agree. The Confederacy reached its zenith at Gettysburg, and it never recovered from that defeat; indeed it never COULD have.