International law is the set of rules, agreements, and treaties that are binding between the sovereign countries which make them or bind themselves by it. Countries come together to make binding rules that they believe will benefit their citizens. Well-drafted international laws promote peace, justice, common interests, and trade.
International law applies to all governments. But it’s up to each government to decide to what extent it will implement and follow international law. A country’s laws apply to citizens and other people that are present in the country. At the same time, it’s up to the country’s governing authority to apply international law and keep their agreements with the other countries that are involved.