And there's the rub.
His job or his opinion regarding American foreign policy. There's debate about which he's testifying to. As a minion, he's supposed to carry out the legal wishes of the elected President.
If he does, in fact, think POTUS did something illegal, then he has an obligation to step forward. If he simply disagrees with the foreign policy of this Administration, which according to the limited, available press reporting, then he's a partisan in uniform.
I don't question his patriotism even if it's the latter case (which is what I think).
Pretty sure Big Army would have preferred he not be highlighting his uniform since it greatly contributes to the view of politiciization of the military.