The information is readily available for people to look up and read. Takes all of a few seconds to find.
This argument does not hold water. It does not make sense to argue that the Confederate States *lied* in their own legislation that they wrote themselves and passed about why they were seceding and in their stump speeches, public speeches, editorials, etc. about why they seceded and about why they started the Civil War. Merely look up the raw material - read the secession resolutions. Read the editorials. Read the speeches. This information is not from a history book someone else wrote years later, some academic's claimed interpretation, etc. - these is their own words that they wrote, said, published, etc. themselves. And I believe them.
They didn't "lie". The Northern states really had violated the fugitive slave clause of the Constitution. They had also supported or at the very least refused to prosecute people in their states who financed or committed acts of terrorism against Southerners. That was all true as the historical record shows. Its just that that was not the reason why they seceded.
Read about Lincoln starting the war deliberately by sending a fleet of heavily armed warships to invade South Carolina's sovereign territory and read his letter of congratulation to his naval commander for getting the war that he wanted to begin.
Read the editorials. Read the speeches. Read the comments from political leaders. Read the declarations themselves and the speeches sent out along with them. Read the Corwin Amendment and Lincoln's first Inaugural Address in which he endorsed it. I have provided a lot of this information in this thread.
You clearly have not been reading all of this thread.
The CORWIN AMENDMENT proves that slavery was not threatened in the US.
And if that isn't enough for you, the UNION had slave states all through the war. In fact the UNION didn't get rid of slavery until about 8 months AFTER it was abolished in the Confederacy.