Disclaimer: I am not American, but I do follow American politics. I know what the Confederacy was, what the Civil War was, and so on.
Here's the question: What specifically are the arguments in favour of not abolishing the Confederate flag?
By "abolishing", I mean basically the same treatment as was done to the Nazi Swastika in Germany following WW2: Can't be publicly displayed, shouldn't be talked about in positive light, etc. What each person does in their own home, e.g. if they are related to Civil War heroes of the Confederacy and want to be proud of their lineage, is their own responsibility. I'm mostly concerned with public displays of the flag. (Yes, there are legal differences between the US and Germany, wherein the US government cannot make it actually illegal to fly the Confederate flag as much as the German government can make it illegal to fly the Nazi Swastika. The question should be interpreted in the context of "inasmuch as is legal in the USA, then...")
(Valid and coherent arguments only please, no "but free speech" etc, unless that's the only real reason; there's lots of things we "could" do and say under "free speech" but don't for various reasons, such as displaying the Nazi Swastika, and I'm not particularly sure why the Confederate flag isn't one of them)
Here's my understanding, to provide the historical context as I understand it to help you all better clear up any confusion I may have: The Confederacy was formed more or less because Abraham Lincoln wanted to free the slaves, and a number of Southern states decided they thought that was a bad idea. Therefore, they seceded from the USA and waged war against Abraham Lincoln's Union over the issue. In the end, the Confederacy lost, the Union won, and we all know the rest of the story.
As an outside bystander, to me the Confederacy represents:
Racism. The entire point of the Confederacy was to continue slavery, and I'm pretty sure even the most white supremacists would agree that slavery (as implemented in the USA) was racist (they might disagree on whether or not that's a good thing, but nevertheless I can't believe anyone would disagree it was racist)
Losing/weakness. The Confederacy lost the Civil War, the Union won.
Aggression/savagery. It's my understanding that the Confederacy started the Civil War, not the Union.
I recognize that history is history, and "those who forget history are doomed to repeat it" and so on. The Confederacy and their flag shouldn't be forgotten to the annals of history, but I don't entirely understand why it's not treated, for example, the same way as the Nazi Swastika, which represents a lot of the same things as the Confederate flag in a lot of the same ways.