Prompt: On the ships anchored at Pearl Harbor this Sunday morning, men are sleeping, eating breakfast, relaxing on the sunny decks, or preparing to go ashore for last minute Christmas shopping. On the cruiser Helena, some of the Marines are getting ready for a softball game. For the second time in three hours, the Ward is on alert, having again detected a strange movement in the water. Upon closer inspection, Lieutenant Outerbridge is stunned to see a stubby black submarine, half submerged. He immediately orders the crew to sink it, and any other submarines they may find. Outerbridge radios the following message back to headquarters at Pearl Harbor:
"We have attacked, fired on, depth-charged, and sunk submarine operating in defensive sea area."
But the Lieutenant's message is decoded very slowly. No one knows to call an alert.
*Depth charge - an explosive device designed to explode underwater

Question: Not knowing about the impending attack, what are the possible positive and negative outcomes of sinking this unknown “stubby black submarine”?