Reading @FukuyamaFrancis's Origins of Political Order, which is brilliant. Here's what he says about legitimacy. "Legitimacy means that the people who make up the society recognise the fundamental justice of the system as a whole and are willing to abide by its rules."

But as societies are inevitably hierarchical, abiding by rules entails recognition of the legitimacy of the ruler. In a democratic society, such legitimacy is conferred through elections. But what about a non-democratic society?

In particular, how can legitimacy of someone's leadership be recognised in the inherently undemocratic international society of states? If, say, Joe Biden proclaims readiness to reclaim America's role "at the head of the table" - how can such a move be legitimated?

Fukuyama skims over this issue because his focus is domestic political orders; yet, his insights are hugely important for understanding the legitimacy (or otherwise) of the global order as such.

On what basis (short of elections) can one claim that US global leadership in a US-led world order is "fundamentally just" and therefore legitimate? A fascinating problem. Any takers?