It also enables novel diplomatic initiatives and strategies. If international relations are defined not just by the interactions of formally sovereign states, but by civilizational fates, this justifies treating states differently depending on their commitment and importance to the civilization.

That’s not novel. That’s how US hegemony has always operated: treating states differently depending on their commitment to Liberalism and “Western values.”

The strength of the Right’s civilizational narrative is reinforced by the fact that a traditional liberal response to a counter-civilizational argument based on universalism has been undermined not only by the Right, but also by critics on the Left and in the Global South, who connect it with Western imperialism.

That’s because that’s what it is. You can call it “universalism” when the US interferes in the affairs of sovereign nations, or unilaterally sanctions or embargos those countries, or even directly overthrows their democratically elected governments and replaces them with a Liberal, US friendly dictatorships, but it doesn’t change the reality and it doesn’t make it right.