What is International Law and how does it shape state behavior?

Samulot: What is International Law and how does it shape state behavior?
What is International Law? How does it shape a state’s behavior? What are some good examples of successes in the international court?

Answering any of these would be great!
Also a case where the court didn’t do well in an argument between two states.

Answers and Views:

Answer by Will
it’s agreed on regulation of nation-state conduct, like the World Trade Organization.