pacifichistorian
Banned
It's possible to get away with it. Morton did. OK, probably not quite so hazardous getting out, but he took a shot at an IJN tincan in the harbor, first...I think any submarine attempting to hide in an inlet or river runs a real risk of running aground. There is also the real risk of the U-boat being captured.
Plus, once the attack is carried out, the whole countryside is alert. Sailing back out through the mouth of the Chesapeake would be near impossible. If the local watermen join the hunt, odds of spotting the U-boat go up a lot.
Michael