Woodward is one of the favorite operatives of one of those factions. While in the Navy he served in Naval Intelligence, he was considered solid enough to go after Nixon and in doing so deflect attention from the active hand some CIA people had in aiding Nixon, and he's been a useful hatchet man for the in crowd on several occasions.
He's doing two things here. First, he's letting it be known that there are people with power who won't stand in the way of criminal charges being brought, and second, since that's possible (how probable? Dunno) he's giving fair warning to those so rabid in their hate of Trump that they've gotten sloppy that it's time to start covering their butts and choosing scapegoats instead of continuing their open attacks.
JMHo
Makes sense...and I so hope you are right!