From Twitter's Glorification of Violence Policy: "Exceptions may be made for violent acts by state actors, where violence was not primarily targeting protected groups."
"Exceptions may be made" doesn't sound like "you can [do it] all you'd like."
Right, but this is another problem which is at the crux of the issue. These exceptions throughout the TOS give Twitter the power to editorialize without requiring them to take on any liability for the content on their site.