Nice try, but this is not suicide. The point of the cartoon is irony. The Klansman is a symbol of racial hatred who historically used lynching as a tool of terror. He is being killed by his own symbol, the Confederate flag. It's a commentary on how hate consumes itself. You're purposely interpreting this as a commentary on suicide. This is like seeing a war movie where a soldier is shot and claiming it's offensive to people who lost a loved one to a school shooting. The method of death is the same, but the context is entirely different.

Shut the fuck up now.