If a big guy throws a punch at you, and you see it coming and hit him first, who started it?
Lincoln launching that war fleet was the "first shot." Had he not done that, there would have been no shots fired at Sumter. Even Major Anderson said this action would cause a war.
"... I had the honor to receive by yesterday's mail the letter of the honorable Secretary of War, dated April 4, and confess that what he there states surprises me very greatly, following as it does and contradicting so positively the assurance Mr. Crawford telegraphed he was authorized to make. I trust that this matter w ill be at once put in a correct light, as a movement made now, when the South has been erroneously informed that none such will be attempted, would produce most disastrous results throughout our country.It is, of course, now too late for me to give any advice in reference to the proposed scheme of Captain Fox. I fear that its result cannot fail to be disastrous to all concerned. Even with his boat at our walls the loss of life (as I think I mentioned to Mr. Fox) in unloading her will more than pay for the good to be accomplished by the expedition, which keeps us, if I can maintain possession of this work, out of position, surrounded by strong works, which must be carried to make this fort of the least value to the United States Government.
We have not oil enough to keep a light in the lantern for one night. The boats will have, therefore, to rely at night entirely upon other marks. I ought to have been informed that this expedition was to come. Colonel Lamon's remark convinced me that the idea, merely hinted at to me by Captain Fox, would not be carried out. We shall strive to do our duty, though I frankly say that my heart is not in the war which I see is to be thus commenced. That God will still avert it, and cause us to resort to pacific measures to maintain our rights, is my ardent prayer.
The vast majority of Lincoln's cabinet also told him that if he sent those ships, it would cause a war. Apparently they all regarded that as the "first shot."
My entire point is to counter this ridiculous notion that the South just wanted to fight an entirely defensive campaign throughout the war and to try an win by attrition a defense of their homeland.
They didn't want to fight a war at all. What they wanted was to run their own affairs and be left in peace by the government in Washington DC.
There’s a lot to be said of what happened at Lexington and Concord in the American Revolution, and by allowing the British to get the first volley in, in essence - the British we roundly considered to be instigators. Every historical book tells that same story and it garnered worldwide sympathy for their cause eventually.
Had the South been smart enough to allow either those ships or the fort to fire first, the diplomatic front of the war with Europe might have been a bit more receptive.
What Lincoln did is tactical genius by sending those ships and forcing Beauregard to make an impulsive and impetuous decision to fire on Sumter, force it’s surrender, and use it as a rallying call to muster gullible volunteers to fight his war. We’ll never know if those ships were sent to evacuate the troops or attack Beauregard’s forces - sure folks can write about the so called intentions all day long and centuries later, but that doesn’t make their presumptions correct.
What Beauregard should have done (hindsight of course), was to allow it’s starved out occupants a surrender - boat them back to DC or Baltimore. Well-clothed, well-fed, treated respectfully and then allowed Lincoln to make his next provocation.
That is, if in fact the South didn’t want a war at all and be left in peace.