When people talk about threat to democracy or institutions, what they mean is threat to democrats or democratically run institutions. 

When democrats storm the White House or try to jail their political opponent or stage a coup on their own candidate, this is good for democracy because it serves the democrat party.

The threats to democracy are always on the republican side. Nothing the democrats do is a threat to democracy.

Since republicans are threats to democracy, the only way we can have a true democracy in this view is if we have a one party state. Like California.

(Elaborated on by Balaji in the recent MOZ episode)