So you're saying that Lee really didn't 'take up arms' against the U.S. because since he wasn't actually shooting at anyone? Would you say that the Chairman of the Joint Chiefs isn't in the military as well? Lee was given command of all Virginia's military forces. He was a general in a military that first planned hostile actions against the U.S. before it even voted for secession. Lee first took up arms in April 1861 by any possible definition of the term.
I doubt it...
;>)
I believe we were talking of field commands. By your reasoning, anyone who disagreed with Lincoln — North, South, or internationally — could be said to have taken up arms against the Union. I was referring to taking up arms in the literal sense (i.e., combat, actually fighting or directing actual engagements).