The US Constitution has become like a toilet paper under the current US Administration, especially, the freedom of speech and religion, as well as, immigration. So, as the US has proven beyond any doubt that it is a lot easier to write a Constitution than to subject itself to live under it. So, until the US put the money where its mouth is, they have no business telling other countries how to govern themselves.
The EU is a lost cause, and it's just a matter of time before it will collapse on its own dead weight. You can't have an economic union without political unity. And the current overrunning of the Muslim migrants, mixed with hidden ISIS terrorists, will only speed up the collapsing process.
And have you noticed that neither the US nor the EU ever dare to tell China, Saudi Arabia, Kuwait, Cuba, UAE, Brunei, Lao, Cambodia, and etc, on how to govern themselves? Anyway, what is your take on this issue?