I don't support the idea of tearing down Confederate monuments by force. I do support the idea of removing these monuments through legally-sanctioned means, and I disagree with the claim that they're 'historically relevant'.
http://news.nationalgeographic.com/2017/08/charlottesville-confederate-memorials-civil-war-racism-history/For one, these monuments were erected not for historical purposes but in response to racial conflict. Many of these monuments weren't memorials to fallen soldiers, but more like politicized responses to racial tension after the Civil War.
Most monuments were dedicated in the decades following the Civil War's end, tied to the 50- and 100-year anniversaries—and to conflicts over race and nationality that were then simmering.
Second, these statues are generally pretty stuffty. The reason why protestors have been able to topple them so easily is because they're mass-produced. Many of them are replicas of other statues of soldiers which have just been recast with bits of Confederate imagery.
Many Civil War commemoration statues—such as the one pulled down in Durham—were cheaply mass produced by northern factories, which simply switched the belt buckles’ insignia to suit Union or Confederate clients.
Finally, the whole purpose of these statues was to intimidate black people. That's why when you look at time-series plots of when Confederate statues have gone up, they peak in the 1910s and the 1960s. Why? Because that's when Jim Crow and the Civil Rights Era happened.
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I'm not saying we necessarily need to 'destroy' these statues but they shouldn't be on public property. They're basically just propaganda from a bygone era that has no business being on state capitols. Move them to a museum or a historical collection.