I'm not even going to entertain this notion. I flatly reject it. I am more like to question the sanity of anyone who suggests a comparison between the two.
Entertain what you want.
Reject what you wish.
Question whatever you like.
The fact remains that Fort Sumter and Pearl Harbor were exactly equivalent in their effect on US public opinion, and were remarkably similar in many other aspects.
To cite just one: Japanese attacked with hundreds of aircraft -- flying artillery, while the Confederate Army attacked with thousands of artillery pieces.
So the suggestion that Fort Sumter was just an insignificant or "minor incident" doesn't stand up to closer examination.