"If slaves had never been brought to these shores, would we have had this war anyway?"
The Civil War of 1860-65 was not the first time Americans wanted to kill or did kill Americans.
1. The colony of Virginia erupted into civil war in the 1600s.
2. The Revolution was a civil war between those Americans for King George and those against his abuses.
3. A civil war almost commenced over the right to distil whiskey.
4. There was almost a civil war over nullification.
5. New England almost joined with England against the rest of the nation over the war of 1812.
There are other examples.
So, no, slavery was not the only issue for Americans to hate other Americans enough to kill each other. Slavery was not the issue the war was fought.