The statues were put up by essentially Klansmen, in direct response to the events in the United States years AFTER the civil war
While I disagree with this, as your definition of Klansmen pretty much includes any Southerner from that era, I will grant you this point for sake of argument. However, considering most of these statues were built quite some time ago, all these Klansmen are dead.
in whole or in part to signal that the communities they reside in stand for the ideology of white supremacy and white nationalism.
This is unsubstantiated assertion. There are other possibilities that you have to consider - that this was at one point true, but with time no longer the case; that it might intend to signal such, but is ineffective at doing so; that for many different people it stands for different things, while you might be correct in case of supremacists, there are many non-supremacists that take different meaning from these.
Nazis today wish to maintain the status quo, to further their own cause of white nationalism.
Status quo is irrelevance and powerlessness of Nazis. Why would they want to maintain this? They can't even openly advocate their view in a public sphere without getting condemned. In this way ANTIFA violence is completely unnecessary and actually counter-productive.
spurious dog-whistle arguments about the historical value of these statues
You might not like it, but these statues do have historical value. You can't argue it away, the best you can do is present arguments why we should disregard this value.
Aside from being disingenuous, these arguments are demonstrably false because history books and museums will continue to exist
It is very easy to demonstrate that a great deal of historical artifacts, places, monuments and so on exist outside of museums. To use your flawed logic - lets tear down White House and replace it with a soulless modern office building, after all it will still exist in museums and history books.
By supporting these arguments and rejecting their clear purpose, you are therefore de facto, in action if not in spirit, supporting the cause of white nationalism.
This is fallacy.
What you say can by transcribed as follows:
Nazi argue monuments are historical
You argue monuments are historical
Therefore you are a Nazi
Nazi like cheese
You like cheese
Therefore you are a Nazi
I hope even you can see how ridiculous and broken such arguments are.
Additionally they serve as false signals to white people that racism is normal, which when combined with all other sources of normalization, contributes to the perpetuation of racism and systemic oppression.
How do you see this actually working? That is, you keep asserting that these statues lead to increased racism. However, you fail to outline any mechanism for this.
Two can play this game: These statues serve as a reminders of regretful past and the necessity to not repeat it to everyone involved. This contributes to reduction of racism and deeper understanding between different racial groups.
Both of these arguments are pure BS. These statues do not change how people treat each other.
No, removing the statues will not solve all of the worlds problems.
Have you paused to consider that removing these statues would CREATE more problems than it solves? One problem I keep bringing up, and you keep ignoring, that reaction to tearing down statues would actually push some, people that see these statues as part of Southern Identity, to sympathize/side with supremacists?