Flying a flag of a regime which betrayed and attacked your nation is corruption, even bordering on sedition. For what heritage does it represent? A heritage of treachery, rebellion, racism, and ultimately defeat. Though that is what it meant in times past. Nevertheless even in this time it is a symbol of rebellion and racism still, specifically the one in South Carolina recently taken down which was put up for to rebel against the will of God and the law of the land for the sake of segregation, which is racism.
As for the so-called rainbow flag, though that be not the topic at hand, I would indeed agree that it should be torn down as well. For it represents both sexual abuse, lovelessness, and ultimately lawlessness. By flying such a flag and the government trying to make sexual abuse legitimate it in fact testifies that the government is close to making itself in totality illegitimate by reason that it shows it hath no law.