The belief that "if you don't have replicates of some subject to use as a control group, you can't know if a theory will make good predictions about this subject" is false.
We only have one universe , with no control group, but scientists have been able to accurately predict things about our universe.

Solomonoff's inductive inference is a mathematical formalization of how to make a good prediction in a unique universe. It is a mathematical Occam's razor: shorter theories give better predictions, provided that they perfectly describe previous observations.
https://en.wikipedia.org/w/index.php?title=Inductive_inference&oldid=471899642

USB? I thought we were talking about TTY here.

According to the Bulletin of the Atomic Scientists and their Doomsday Clock, it is 5 Minutes to Midnight:
http://www.thebulletin.org/minutes-to-midnight/

They also mention the main non-nuclear threats like global warming and the other WMDs.