"rules-based order" is one of those phrases like "rogue state" and "international community" that is usually though not always used by mouthpieces and fellow travelers of the American hegemony for propaganda purposes. There is a certain social group of bureaucrats, journalists, think-tankers, and various other sorts of nomenklatura who swirl around Washington D.C. and seem to suck these loaded terms into themselves along with their mothers' milk. They do not necessarily intend to use these phrases as propaganda - often they use these terms because they genuinely buy into the ideology behind them - but the ideology itself makes those terms propaganda nonetheless.