Saphroneth
Banned
He'd been repulsed, yes, but he ended up on the James.McClellan was not ordered off until after he had been repulsed by Lee.
The main one, presumably, being that Grant could get himself reinforcements without having to beg for months.There are several differences between 1862 and 1864 that you are ignoring.
And why do you think that might be different in 1862? McClellan was a siege specialist.In 1864, Robert E Lee said ""We must destroy this Army of Grant's before he gets to the James River. If he gets there it will become a siege and then it will be a mere question of time."
Lee explained to Davis that McClellan would advance "post by post" and that they would have no way to stop him, which is why they were so happy when McClellan was withdrawn. Basically the same situation - a siege is irresistible when well prosecuted - and highlights the parallels, much like Halleck's letter about how it would be best to withdraw Grant (in the same way they withdrew McClellan):
"Entre nous. I fear Grant has made a fatal mistake in putting himself south of James River. He cannot now reach Richmond without taking Petersburg, which is strongly fortified, crossing the Appomattox and recrossing the James. Moreover, by placing his army south of Richmond he opens the capital and the whole North to rebel raids. Lee can at any time detach 30,000 or 40,000 men without our knowing it till we are actually threatened. I hope we may yet have full success, but I find that many of Grant's general officers think the campaign already a failure. Perseverance, however, may compensate for all errors and overcome all obstacles. So mote it be. " - Maj Gen Henry Halleck to Maj Gen WT Sherman, 16th July 1864