“I am sure, with an unbiased jury, I could prove in a court of law beyond a reasonable doubt that Lee committed treason.”
That reminds me: “No Person shall be convicted of Treason unless on the Testimony of two Witnesses to the same overt Act . . .”
Who are your two witnesses?
How about Burnside and Pope? Having gotten their butts kicked by Lee on the battlefield I imagine they would have a reason to get even. And they can certainly testify that Lee waged war on the United States.