My ancestor fought for the Confederacy. He believed in the cause, and didn't own slaves. In fact, none of my family owned slaves. We were what the slaveholders would have called "poor crackers." My ancestor fought for the South because it was his home.
Slavery was a despicable, unchristian evil, but like it or not, it was a vital part of the Southern economy. The North was determined to abolish it all at once, which would have, and eventually did, wreak economic havoc on the South, putting us probably a quarter of a century even farther behind. A gradual emancipation would have been a far better solution, but the North was determined to have its way, and the South would not allow state sovereignty to be violated.
To me, the Confederate flag represents heritage, sacrifice, and love of liberty. That last one is ironic since most Southerners would never allow blacks their liberty. There were free blacks, however, who fought underneath our banner. If you ask me, a little Southern determination to be free would be helpful in our present time of unprecendented government intrusion.