What was the greatest chance for a Confederate victory?

The French were out of Mexico by the time Gettysburg happened.

And? Neither was Lee. ROmmel was in control of all the Axis forces in North Africa.

Lee only had command of one army now he did do a lot with that army but he did not command all confederate forces.

No not at all.
Also guys remember that there was a huge difference between command in the Civil War and command in WW2. Generals in WW2 usually commanded forces across a wide front, while overall command during the Civil War might as well have been a ceremonial position because your generals in the field had pretty much free reign.

For the most part, yes.

The French invaded Mexico city on 7th June 1863. Less than a month before Gettysburg. They didn't pull out until 1867. Pullouts back then weren't like modern day pullouts. They didn't last for years, the invading army just left.

But he was in overall command of basically the Army of North Virginia, one of the most primary of forces in the CSA Army.

Primary force for the Confederates in Virginia, not the West, which was a much bigger and a front much more important than the East. And he only became commander of the Army of Northern Virginia on May 31, 1862.

However, do you deny the fact that the Army of Northern Virginia under his control was a critical part in the war?

Of course it was. But to blame him for the war is absurd! If anything, the war was lost by the Army of the Tennessee and its commanders. It was won and lost with Sherman and Grant in the West, it was a stalemate in the North until the West had already begun to crumble.

That is why I blame Davis. Always gave the position of army commander to his old West Point friends (Braxton Bragg).

So let's say the Union do achieve taking the Mississippi River. Yet by then the CSA has taken DC, New York City, and Philadelphia.

You have no logic backing up claims. I can say that both NYC, Philly and DC are all fortified, on a river (or island) thus bringing in naval support and a supply route, and any such invasion of the North brings the massive Army of the Potomac to bear down on the Army of Northern Virginia and thousands of recruits and supplies. Any protracted siege will be bad for Lee, as the AofP will simply catch up to them and force an engagement unfavorable to Lee, as well as the fact even if he wins such a battle, he is cut off from supply lines and reinforcements. The farms of Pennsylvania can only sustain an army for so long, and when summer is over, there will be no more food to pillage.

And Rommel was in overall command of the Afrika Corps, which was arguably the most important force on the western front at the time. He was also in command of the army defending the French coast during D-Day.

This whole arguement is rediculous Lee is the only reason the war lasted as long as it did without him Richmond would have fallen in 62. I am really becoming sick of argueing this point because none of this matters as long as the CSA lost in the west no matter how hard they fought in the east they would have been sourrounded and cut off.

I concur. Without Lee, the war would have been over long before than when it did end. For example, in the Peninsula Campaign, when Lee took charge, McClellan's army was 6 miles from Richmond, and they could even here the church bells. By the end of the 7 Days Battle (which the Confederates mainly lost because of Jackson, no joke), the Union were at there starting base on the James River at the beginning of the Peninsula Campaign.