The US does - as usually - not treat Copyright (or any other IP law) the way the rest of the world.

With the exception of the US, there's no "Copyright Office" where copyright is registered at. Copyright is automatically given for any work having sufficient "level of art" - a bar which is very low. It is not even required to state © for the work. However, if a work indeed has sufficient "level of art" can only be determined in an IP court of law.

R.I.P. Copyright

It seems to me that copyright doesn't exist anymore as a reasonable notion and effective right for an individual creator--A.I. being the final stake through the heart