They’re different things, of course, but both are used foreign policy. Consider Vladimir Putin’s “special military operation.” It’s just a euphemism for Putin’s genocidal war against Ukrainians.
The global West is reluctant to face off against Russia for fear of starting a Third World War despite the fact that Russia’s recruiting of Belarus’s and Syria’s troops in its adventurism makes it a de facto World War at least on the aggressor’s side.
Since Russia is targeting civilian populations, it is violating international law. Enter the metaphor. When one breaks the law, one can expect intervention by the police. In this case, the police must be the US and/or NATO. Police intervention need not be activated by an attack directly on the policemen. It should be enough that a nation is violating international law by committing a genocide, violating the Geneva Convention, and so on.
Thus, intervention on the behalf of Ukrainian citizens is not a declaration of war on Russia but simply a “police action.” Metaphor, meet Euphemism.