[drran]

> That aside Russia coming up with it's own reasons for engaging in war with a country is different than Russia having internationally recognized reasons for engaging in war with a country.

Can you explain? Is there another internationality, except UN, which has authority to allow wars?

[torstenvl]

> Is there another internationality, except UN, which has authority to allow wars?

Kind of. International law is made up of both treaties and customary international law, which is (to oversimplify) basically a distillation of state practice. Think of it as almost analogous to statues vs. common law.

For example, while the U.S. is not a party to the U.N. Convention on the Law of the Sea, it recognizes most of its tenets as customary international law. (This is also why it regularly conducts freedom of navigation passages in the South China Sea, to prevent China's ownership claim from becoming customary international law.)

If a large number of nations (say, NATO?) agreed that another lawful basis for the use of force (LBUF) existed, beyond the right of self-defense or an UNSCR, that could become customary international law. The hot topic in this area right now is humanitarian intervention, which NATO cited in its Kosovo intervention and which the UK recognizes as a CIL LBUF. This gets meta real fast, since even though a large number of nations reached consensus on using it as justification for Kosovo, they haven't reached a consensus that there is a consensus on using it. Only the UK explicitly recognizes it as CIL, last I checked.

So what you see instead is this kind of academic song and dance where, e.g., the U.S. de facto is using humanitarian intervention to justify intervention in Syria but de jure relies on a mildly stretched interpretation of self-defense instead.