Language is a system of symbols used for communication. A flag is a symbol, a word; it represents an idea and sends a message. This is why flying a Confederate flag is protected as freedom of speech. The Confederate flag is basically the n-word. It is a racist symbol. That flag represents the Confederate States. The Confederate States declared their cause when they seceded from the United States. That cause was white supremacy. That's what the Confederate flag stands for.
The South seceded from the United States because of the rise of the Republican Party and the election of a Republican President, Abraham Lincoln. In their declarations, the Confederate States asserted that they opposed the Republican Party for the following reasons: “[its leaders proclaim] the equality of the black and white races,”(Georgia) “It advocates negro equality, socially and politically,”(Mississippi), “they have denounced as sinful the institution of slavery,” and for “proclaiming the debasing doctrine of equality of all men, irrespective of race or color… [and] the recognition of political equality between the white and negro race.”(Texas) The Confederate States seceded because a Republican was elected President and the Republican Party did not stand for white supremacy.
Beyond seceding because of their objection to the non-racist nature of the Republican Party, they declare that their own cause is white supremacy and African slavery. In their declarations, the Confederate States assert that they stand for “the subordination and the political and social inequality of the African race”(Georgia) and for “protecting the institution known as negro slavery—the servitude of the African to the white race within her limits—a relation that had existed from the first settlement…and which [Southern people] intended should exist in all future time.”(Texas) Again, they say, “Our position is thoroughly identified with the institution of slavery…. none but the black race can bear exposure to the tropical sun…and a blow at slavery is a blow at commerce and civilization.”(Mississippi) Again, they declared: “We hold as undeniable truths that the governments of the various States, and of the confederacy itself, were established exclusively by the white race, for themselves and their posterity; that the African race had no agency in their establishment; that they were rightfully held and regarded as an inferior and dependent race, and in that condition only could their existence in this country be rendered beneficial or tolerable.(Texas)
In their own declarations, the Confederate States identified their own cause with that of white supremacy and the subordination of the African race. The Confederate States declared their cause to be that of racism! They did not speak of abstract “states’ rights” or any such thing. They identified their cause with slavery and racism. Therefore, the Confederate flag, as a symbolic representation of the cause of the Confederate States, is inherently a racist symbol. When you wave a Confederate flag, you are shouting the n-word. When you wear clothing with a Confederate flag, you might as well be wearing a KKK hood.