To my knowledge, despite often facing odds of 2-1, 3-1, and 4 or 5-1, Lee never lost a battle. He could fight to a draw, gather his men and move on to the next battle the next day.

Lee was very aware of the limitations of the South, and had the vote to secede changed by a factor of one vote, Virginia would have remained in the Union.

To prolong a war for two to three years, despite being outnumbered, consistently, with a very poor manufacturing base, and having almost all trade blocked, is a feat of greatness. The cause was disasterous, the man is remembered because of his ability, not which side he fought on.