The laws of physics are inflexible.

The laws of man, including international law, treaties and borders, are made up and can be change with enough will or force.

I mean of course they can but that doesn’t mean it’s the right thing to do, or even productive towards a country’s ends, or beneficial to then international community. Peace relies on honoring agreements. If you see countries start breaking their obligations, stand back and go “whelp that’s guns for ya” I’d call that a pretty regressive take on international relations.