That riot had nothing to do with political parties, you’re being disingenuous.
The Republican Party contained a substantial number of abolitionists and Abraham Lincoln was the first (and very nearly the last) Republican president. Our party’s first president was murdered by a Democrat. Memories have faded and times have changed, but you need to know and honor your past.
Besides, the people who are likely most interested in waving around the Confederate flag are Democrats and proggies there to disrupt Trump’s rally.