Do you know the "actual philosophy" behind the swastika?
Yeah I do. Peace, good luck, auspiciousness, well being.
It's an ancient symbol common to many religions around the world, going back 5,000 years. The "real" meaning of a symbol is irrelevant when it means something else entirely to most of the people.
I'm curious, why is everything "irrelevant" to you? The real meaning of a symbol means a great deal more to those with whom it originated than those with whom it didn't, and whatever alternate meaning it is assigned by those outside of the origin is irrelevant. So, when the Army or Northern Virginia crafted that Confederate battle flag, they never intended for it to be a sign of slavery or racism. Period.
According to the historian John Coski, the flag was more a sacred symbol to southerners than one of white supremacy during reconstruction. That's what William Porcher Miles had in mind when he crafted the flag, it was intended to bear a sort of innate religious significance. I can't find any accounts where the flag was ever used as a symbol of oppression during or after the Civil War. It was a battle flag, nothing more, nothing less.
The meaning of a symbol can be misattributed, you know like the swastika. Once a symbol of luck, peace, and well being; it was perverted into one of murder, suffering, slavery, repression, genocide, and conquest. Likewise with the Confederate Battle Flag. A symbol of intended religious significance has been perverted into something representing slavery, racism, and oppression. See the pattern there?