From an Army officer:
I’d like to offer one other insight.
I suspect that by asking for a court-martial instead of non-judicial
punishment, the SEALs are maintaining that they are absolutely innocent
of striking the detainee after he was subdued. They would be foolish to
do this as a “How dare we get punished for one little punch” statement
— they know that a court-martial will only assess the binary “did it
happen/did it not happen” aspect and not whether it’s a big deal in the
grand cosmic scheme of things. And being found guilty at court-martial,
even for a single punch, would be devastating for anyone’s future. I
think the SEALs will argue that the bloody lip was caused 1) by someone
else at the detention center or 2) by the detainee himself, who knows
the knots we tie ourselves in over these kinds of things.
Finally, I’d submit that someone who got punched in the face by a Navy
SEAL would probably end up with much, much worse than a bloody lip.