"The first recorded shot by the Union was Fox firing on an unarmed passenger ship waited outside the entrance to the harbor for permission to come in. Fox did not know what ship it was."

So are we saying the actual "first shot" was fired by a Union Man of War against an unidentified and unarmed passenger ship? Or was the Bombardment of Sumter already underway?

This statement would in fact seem to indicate that there was some sort of "patrol" of the Harbor entrance and that ships once inspected and their purpose determined were allowed to enter the harbor.

Clearly Fox was not intending to abide by such formalities. I guess what I am wondering is if the narrow deep water Harbor channel could have been "Boomed" with Chains and anchored boats to prevent unauthorized entry? That would have prevented larger vessels from making a sneak run into the harbor as Fox had planned.

It would seem that Beauregard et. al. did not believe that they could stop the reinforcement of the Fort Sumter garrison by the sea. After all a wooden ship is a hard things to sink unless a lot of damage can be inflicted on it.

One would have though that after the "Star of the West" incident, the military would have taken greater pains to strenghten the harbor entrance defences other than by just land batteries alone. Add to that the ample forewarning that they had that this fleet was on its way with the intentions to relieve the Sumter garrison, one has to wonder why it was felt necessary to fire upon Fort Sumter itself in order to settle the matter.