"Sneak attack" makes no difference.
What matters is that it was a direct military assault, not accidental, not unintentional and not by disorganized militia.
It had a military commanders, a military objective and was fought on military terms.
The only difference I would acknowledge, but you would certainly deny, is that Pearl Harbor was "state on state" military while Fort Sumter was "rebellion" or "insurrection".
Indeed, if you ask the question, "why in the world would the Confederacy go to the trouble of formally declaring war on the United States?", May 6, 1861, one answer is to gain recognition that they were, indeed, a "state" not just some insignificant rebellion.
So, if for these purposes we acknowledge the Confederacy's "statehood", then Fort Sumter was, like Pearl Harbor, a "state on state" military assault, and each began the greatest wars in American history.
I reject your entire desperate self-serving premise as so utterly absurd, it's not even worth a mild rebuttal. Conflating Pearl Harbor with Fort Sumter is Mad Magazine satirical revisionism run amok.
The planned domestic political and military coercion and tyranny of Northern aggression was met with a stout defense and resisted with force. Lincoln: Heads we win; Tails you lose.
Like any other Victor, Northern "historians" were tasked with portraying slan and spin that was required to completely shut down and censor any inconvenient and abbiguous truths.