international system is goverened by anarchy (realism), not by law and co-operation (liberalism)

I have to argue that the International system is governed by anarchy (realism) and not by liberalism.
I need a 200 word answer of why. but you can’t answer this using a case study or actual evidence of the theory in real world examples, but rather use the theory itself to answer the question. Use the theory in favor of the argument.

It doesn’t have to be written academically. no citing, no readings. Just write it in a way that I can understand how to argue this without using real world examples.