In fact, Lincoln did not know for certain what the Confederacy would do in response to his resupply mission to Fort Sumter.
What Lincoln did know was that he had to do something soon to prevent starvation and surrender of Sumter.
If Confederates allowed Lincoln's resupply mission, then status quo was maintained, and all Upper South and Border States remained in the Union.
And that was absolutely the preferred outcome, because it meant that over time the Deep South might be slowly persuaded to return to the Union fold.
Or, Congress might eventually decide to authorize secession, at which point Lincoln's responsibility in the matter was over.
But if the Confederacy chose an act of war to seize Fort Sumter, then war would begin because that's what the Confederacy wanted.
rustbucket: "He also succeeded or lucked into losing the battle of Fort Sumter, which meant that he didn't have to keep ferrying supplies to Sumter and defending the fort. "
There's no way to "succeed" in losing a battle, that's just ridiculous.
General Winfield Scott and others advised Lincoln it would take 20,000 US troops (an understatement) to hold Fort Sumter, at a time when the entire US Army was only 16,000 and most of them scattered in small units out west.
At the same time, the Confederacy had already called up 100,000 troops, so there was no possibility -- zero, zip nada -- that Lincoln could even fight, much less win, a battle for Fort Sumter.
What Lincoln could do, and did, was attempt to resupply Sumter, and in the process learn if the Confederacy intended to start war.
As it turned out, they did.
rustbucket: "Remember too that Lincoln had secretly pulled one of the key ships [Powhattan] from the Sumter expedition without alerting Fox and sent it to Fort Pickens.
The Sumter expedition was too small to succeed..."
Neither one extra ship, nor ten more, would have made any difference at Sumter -- Lincoln's ships were sent to resupply not invade.
They could not, and would not, fight their way in or out.
rustbucket quoting: "Mr. Lincoln saw an opportunity to inaugurate civil war without appearing in the character of an aggressor." [Source: Providence Daily Post, April 13 1861].
Since Lincoln's actions were lawful and the Confederacy's a premeditated act of war, Lincoln did not "inaugurate" anything.
rustbucket: "Lincoln needed to (and did) keep Congress out of the way so he could take actions such as invading the South (Virginia, at least) that committed the country to war."
On April 15 Lincoln set the date for Congress' return as July 4.
Then, after Lincoln's action:
None of the subsequent Confederate actions -- after Lincoln's call on April 15 -- were known by Lincoln at the time.
rustbucket: "Given the natural patriotic feeling in the North generated by all of this, Congress would have no political will to oppose his actions."
Most Northerners, even Democrats, believed the Union should be preserved and its laws enforced -- yes, certainly, peacefully if possible, but if not, then by such means as proved necessary.
They did not need Lincoln to tell them that.
rustbucket after quoting Anderson: "Anderson was not the only one to recognize what Lincoln was doing would start a war.
Lincoln on April 5 gave a verbal order to reinforce Fort Pickens without telling the Confederates."
Lincoln ordered the Powhattan to Sumter, not Pickens.
Lincoln notified South Carolina Governor Pickens of the Sumter mission on April 6.
Jefferson Davis immediately ordered war to begin, a move endorsed by the Confederate cabinet on April 9.
rustbucket: "The Confederates had promised not to attack Fort Pickens if the Union did not reinforce it.
A violation of the truce could result in a shooting war."
All such demands by Confederates were acts of rebellion and/or war against the United States, period.
rustbucket after quoting various officials: "These three key guys recognized at the time that Lincoln was taking actions that could provoke war.
Obviously they hadn't gotten the message about who started the war."
There is no lawful way to demand the US government not protect, supply or reinforce its property and personnel.
Any such demands are illegal acts of rebellion and/or war.
The perpetrator was not the Union, but the Confederacy.
rustbucket: "The Official Records show that Union forces started reinforcing Fort Pickens on April 11.
That was before the South fired on Fort Sumter.
So, if Captain Adams was right, the North had already declared war on the South before the attack on Fort Sumter."
First, see my comment above.
Second, by April 9 Davis ordered and his cabinet confirmed war to begin at Fort Sumter.
Third, as it happened, the Powhattan's voyage to Fort Pickens was a mistake in communications, which Lincoln attempted unsuccessfully to correct.
So, if that was the Confederacy's excuse for war, it yet again demonstrates they were eager, itching and cruisin' for a bruisin'.
Lincoln ordered the Powhattan to Sumter, not Pickens.
First of all it was spelled Powhatan. Second of all, Lincoln did sign orders that ended up sending the Powhatan to Fort Pickens. When Navy Secretary Welles discovered that the ship wasn't going to Fort Sumter as he thought, he went to see Lincoln. From "Days of Defiance" by Maury Klein:
Welles marched to the White House, where he found Lincoln alone at a table. The president looked up from his writing, saw the dark cloud on Welles's heavily beared face, and sighed, "What have I done wrong?" Welles showed him the papers [signed by Lincoln] and pressed for an explanation.
Lincoln had signed orders without reading them. From "Days of Defiance" again: "Lincoln looked mystified and took the whole blame for the mixup on himself." Even after this, Lincoln still kept the Pickens mission secret from Welles. The Pickens mission had been planned without Welles knowledge even though it involved Navy ships and officers.
Lincoln then gave orders to Seward to return the Powhatan to Captain Mercer (i.e., to the Sumter expedition). Seward sent an order to do just that. Seward signed the instruction, "Seward," and did not say this latest instruction was at the order of Lincoln. By the time the order reached the Powhatan, it had already sailed on its Lincoln-authorized mission to Fort Pickens. The note from Seward was carried on a fast ship that managed to catch the Powhatan, but Porter, the man in charge of the Powhatan, ignored it saying that he had received his orders directly from the president, who had not rescinded them. He proceeded to Fort Pickens where he tried to enter Pensacola Harbor flying English colors, a false flag act. In July, Lincoln stonewalled Congress about his orders that violated the armistice/truce at Fort Pickens. No copy of the secret orders survived.
Hell of a way to run the government.
... the local elections that week [rb note: late March or early April, I think] went badly, as Republican candidates lost in Connecticut, Ohio, Brooklyn, Rhode Island, and St. Louis. "Thirty days more of 'Peace Policy' at Washington," one Ohioan warned Lincoln, "and not only the Republican Party, but the Government itself will be gone to destruction." ...
The mounting pressure to act dismayed Lincoln. He had struggled to keep the door open for Seward's policy of delay as long as possible. The Pickens expedition was part of that effort, its secrecy designed to prevent the Confederates from getting wind of the mission and attacking the fort before the relief force arrived. To that end, the president had dissembled with Welles, feigning ignorance of orders in that simple, straightforward manner he had perfected to an art form.