The order established since 1945 has been focused on preserving peace between the major states, supported by an infrastructure of institutions and rules, and led principally by the US and its allies.

But as China becomes the second-most powerful state in the world and the US - especially since the election of Donald Trump - retreats from its leadership role in the current international system, there is much debate about the survival of a ‘rules-based’ international order. 

Individual institutions also face their own unique sets of challenges and pressure to reform. NATO’s purpose is being debated and its funding is under scrutiny, bilateral relationships between major powers are seen to be undermining the United Nations (UN), while the G7’s relevance is under threat from the G20, whose growing economic influence is also affecting the remit of the World Trade Organization (WTO) and the International Monetary Fund (IMF).