Sure looking from the outside we can tell them that they are going to fall because of histroy. But they can tell us the same thing using other Superpowers as examples, Britain, Holy Roman Empire, Ottoman Empire.
The moral compass can be explained no matter where you come from and people standing on the outside aren't going to agree. Everyone can justify their actions with an inner moral code. Some codes are just more twisted than others...but that's a judgement too :)