Optics in politics matter a great deal, which explains why gatherings of world leaders – such as the G20 last week – are so closely scrutinised. The media and the public believe they can glean more nuance from snapshots of unguarded moments than from hours of carefully calibrated speeches.
A photograph from the G7 summit in June this year of a recalcitrant Donald Trump sitting surrounded by world leaders, looking annoyed and exasperated, seemed to say something broader about the state of US international relations. A year ago, at the G20 summit in Hamburg, a camera captured German Chancellor Angela Merkel rolling her eyes during a conversation with Russian president Vladimir Putin, which seemed to sum up their relationship perfectly.
At this year's G20, the focus was on Mr Trump muttering: “Get me out of here” to aides as he left the Argentinian president alone on the stage, and on Saudi Arabia's Crown Prince Mohammad bin Salman high-fiving Mr Putin.
But perhaps the most striking aspect of the gathering of world leaders was the summit itself. Politicians from the most industrialised countries had flown to Buenos Aires to solve problems together, only to demonstrate that many barely believe in its founding principles. The basis of multilateral co-operation, the idea that there are rules and that even those with the military and economic strength to defy them ought be bound by them, was starkly absent from the hardest questions the summit had to consider. On the optics of last week's G20, multilateralism has fallen dangerously out of fashion.
For the first time in many years, the leaders of three of the world’s most powerful countries – the US, China and Russia – are actively committed to undermining or overturning the very principles of multilateralism.
All are chafing under the yoke of international rules – something that is most surprising for the US, since it was one of the principle architects of the current world order. But under Mr Trump's presidency, diplomacy has become more transactional.
For Russia, the international order is constricting and Mr Putin has no intention of being hamstrung by it. Again and again in recent years, he has overturned European assumptions that there is a limit to what Moscow would dare to do. Russia did so again days before the summit when it arrested Ukrainian sailors navigating the Kerch Strait near annexed Crimea.
Of the three, China is the most intriguing, openly using the language of the international order while subverting and defying it. China has given the appearance of being dragged reluctantly into Mr Trump's trade war but in other aspects, such as navigation through the South China Sea or the abuse of intellectual property rights, it has openly defied the international order. When the rules-based system has collided with its own goals, as it did in 2016 when a tribunal in the Hague ruled in favour of the Philippines over a territorial dispute, Beijing has simply but firmly ignored it.
For the leaders of all three countries, the rules of the game are conditional and open to interpretation.
Because of this, the G20 and other multilateral institutions such as the United Nations and the World Trade Organisation have been undermined. Multilateral structures are being sidelined in favour of bilateral deals. The major problems of the world, which industrialised nations are meant to be gathering to resolve, are actually being dealt with on a one-on-one basis.
The major issue of the G20, the US's trade war with China, was not solved by the G20 but by Mr Trump and Xi Jinping meeting face to face and agreeing to a truce – after the summit had ended. The final communique from the summit could do no more than make passing reference to "current trade issues".
The crisis in Ukraine was barely discussed and the communique made no mention of it. Even a spokesman for Ms Merkel's party later said Mr Putin had “escaped nearly unscathed” from the summit. The G7 in June similarly ended in disarray.
Institutions are also being undermined. Mr Trump demanded – and last week finally got – a pledge from other countries to reform the WTO, the basis of multilateral trade and an institution Washington has long held in contempt.
Even the word multilateralism is becoming taboo, with the US insisting the final G20 communique say the multilateral trading system was “falling short”.
Such disdain for multilateralism has thrown some of the incongruences of the summit into sharp relief.
Summits like the G20 increasingly look like the vast folly of a pampered elite: talking climate change while flying thousands of people across the world to Buenos Aires for a few days; talking global prosperity while Argentina spends millions to host and protect the summit, in the midst of deep, ravaging austerity cuts; talking consensus while western powers squabbled all night to agree a short statement – merely words, recall, not even policies – for the final communique; and talking the importance of multilateralism while major decisions were done in bilateral meetings.
That multilateralism is in crisis is hardly in doubt. Although France's president Emmanuel Macron tried valiantly to defend it at the summit, the momentum is against him.
The reason is simple: there is no one willing to defend the system. Mr Trump, who made it a mark of his political character to be an outsider, seems to be actively committed to undermining international institutions.
Yet it was precisely to stop this kind of zero-sum negotiation that these institutions were originally set up and international rules created. Countries unbound by a global order tend to do what is best for them in the short term and ignore what happens to others in the longer term.
To see the dangers of that thinking and why there is no alternative to multilateral institutions, one need only look at the major crisis in the region, the Syrian war.
With no framework in place within which to seek peace, outside countries muscled in, all seeking to serve their own interests. The regime has repeatedly flouted the rules of war and international humanitarian law, knowing there is no one to hold it to account. This jockeying for swift victories and dominance over rivals is in large part what helped morph the uprising into a global war.
Without rules, there is a Hobbesian quality to politics, whether it is expressed in economic costs, as with the US-China trade war, or political clashes, as in Ukraine, or military conflict, as in Syria.
Complex challenges require co-operation, and co-operation requires that sometimes the most powerful agree to be reined in by the system.
When everyone simply fights their own corner, the optics and the politics rapidly get ugly.