The Union never declared war. It was the position of the United States government that the states had rebelled against the duly elected government of the US. Lincoln, with the support of congress and most of the north, used his constitutionally delegated powers to call out troops to defeat the rebellion and restore the constitution as the supreme law of the land. Just as Washington did to the whiskey rebellion.
I know in another thread you state you have only been studying this for a few years. As someone who has studied the civil war, and history in general, both professionally and for pleasure, may I suggest you print and read every rebelling states declarations of succession. While doing this underline every instance of the use of the word slave, slavery, anti-slavery, and any other variations. Also underline every time the word tariff or tariffs or any other variations are used. Then count the underlined slave and tariff words and I’m positive you will find a huge disparity between the word count. With slavery and its variations grossly outnumbering tariffs. Perhaps that will give you a hint on why the states secceded.
Yes, that was a carefully crafted legal fiction. Lincoln had his legal argument lined up long before the war started. This is one reason he refused to meet with the Representatives from the South, and instead pawned them off on Seward, I think.
He was working hard to create the illusion of deniability. Also by refusing to call it a war, he didn't have to get authorization from Congress, which in any case he had waited till they adjourned before he sent his war fleet to Charleston to threaten the Confederates.
But to get back to the point, so the Union fought because someone rebelled? Not because they had slavery? So what does that do to "The Union fought to abolish slavery!" meme? Seems like it blows a hole in it.
I know in another thread you state you have only been studying this for a few years. As someone who has studied the civil war, and history in general, both professionally and for pleasure, may I suggest you print and read every rebelling states declarations of succession.
I am familiar with them. My position is simple. The Declaration of Independence asserts that every people have a right to independence, and it does not require them to have a morality approved by others, they possess the right of independence none the less.
Whether the South left for immoral reasons is immaterial to their right to have independence if they want it. The Brits thought the most immoral thing a man could do was to repudiate his natural allegiance to the King, and so the morality of the seceders is therefore irrelevant to their right to do so.
Perhaps that will give you a hint on why the states secceded.
If a woman does not want to remain with her husband, should she be forced to stay with him if we don't approve of her morality?