The South had a big-ass revisionist history streak in the wake of Reconstruction, where they did everything they could to muddy the reasons and actions behind the Civil War so that the Confederates looked neutral at worst, heroic at best. That's where bullshit arguments like "states' rights" come from and why there are so many memorials to Confederate leaders all over the country. That's had far-reaching consequences across much of how American history is taught, to the degree that some folks aren't even aware of the specific reasons WHY the South tried to leave the country.

Of course, some people know the real reasons, but support them anyway. Because they're racists.

Imagine claiming you are patrotic, but bringing to the Capitol a flag that not only represents hate and slavery, but also treason to your country.