Actually, the Southern Militia first fired at The Star Of The West - a steam boat, filled with an additional 200 soldiers and munitions, heading to reinforce the Union Army at Fort Sumter, after Major Anderson agreed to vacate. But Major Anderson obviously had no intention to vacate, and had been procrastinating for 2 months. This violation was clearly an act of war. So the Southern Militia fired across their bow (meaning they did not hit it ) to make it turn back. Then they fired at Fort Sumter (But again, never hit any of the soldiers) to make them vacate. Upon leaving, the Union Army "Grounded" their cannons (as they had done at Fort Moultrie) so that the South would be unable to use them. That's when the clumsy Yankees accidentally lit off an ammo supply, which exploded and killed two of their own soldiers.
But blame that on the Southern Militia, too because you've been spoon fed pseudo history.
So to answer your first point, YES Fort Sumter DID fire on itself.
As far as Western Expansion goes, there were two sides of the political aisle trying to gain political power. I agree with that.
What I don't agree with, are the labels traditionally used. "Free States vs Slave States."
It was the Union vs The Confederacy. The debate over keeping slaves in the West is a red herring. Or have you forgotten about how many slaves were freed in the South BEFORE the Civil War? Former slaves who were FREE to purchase land, own businesses, and even buy slaves themselves (such as William Ellison who made a fortune making and repairing cotton gins).
Your third point references Frederick Douglass's story, which is another fairy tale.
The man he was sent to work for, Edward Covey, studied working conditions to see if they were too rough. He worked alongside field hands, to see if they needed regular breaks. In other words, he was an efficiency expert.
He also monitored the worker's behavior secretly to see if they would work or slack off.
The first day Frederick Douglass was sent to him, Mr Covey gave him a simple task of gathering firewood. He even supplied Fred with an ox and a cart.
But Fred wasted the whole day, failing to gather any wood at all. Then blamed the ox saying it overturned the cart, damaging it.
Obviously, Mr Covey had seen what actually happened - while not recorded in the pseudo history books you read - can be deduced to that Fred made up an excuse for wasting hours and hours, doing no work at all.
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