You completely missed the point. Whether certain actions are "OK" are not is utterly irrelevant in geopolitical affairs. Sovereign states will always act in their (perceived) best interest regardless of legalisms or moral codes. Justifications are then manufactured for public consumption.

Ultima ratio regum.

As for international frameworks, how should the Non-Proliferation Treaty be enforced? If a country violates it then what should the consequences be?

https://disarmament.unoda.org/wmd/nuclear/npt/