What if the American ships at Midway carried the later 40 mm and 20 mm anti-aircraft fit?
Short answerThey would put up about three times as much anti-aircraft fire, though Japanese pilots could still do well.
NotesThe later 40 mm and 20 mm fit is estimated to triple American anti-aircraft fire at Midway. Japanese pilots are still expected to perform well. More defensive fire would make their task harder, without establishing an exact change in losses or the battle's outcome.