This century has one overarching theme: the fall of the west, that is, the US and its European allies. Every major crisis accelerates the unmistakable trend. The war in Gaza is just the latest manifestation. Western newspapers are now littered with articles full of the panicked realisation that more is buried in the rubble of Gaza than just thousands of unidentified bodies. “The damage to Israel’s reputation,” writes Matthew Parris in the Times, “so much less manifest than shattered hospitals in Gaza, is incalculable.” Yes, but it would be an error to believe that it is Israel’s problem alone. When the former Palestinian negotiator Diana Buttu told me this was an “Israeli-American attack”, she summed up what much of the world sees. That Israel faces a catastrophic strategic defeat and reputational calamity is dawning on even its most ardent supporters; soon it will be widely understood that this applies to its western cheerleaders, too. The west’s decline long predates this current crime of historic proportions, but it is the radical right which has, to date, monopolised this conversation. For it, the explanations for the downfall are, variously, immigration, multiculturalism, Islam, “wokeness”, “gender ideology”, the disintegration of the nuclear family, and so on. Liz Truss’s forthcoming book, Ten Years to Save the West, raging against a supposedly leftwing establishment blocking free-market innovation, is the latest addition to this genre. In fact, the explanation is really rather simple. In the aftermath of the Soviet collapse more than 30 years ago, western elites became intoxicated with a premature triumphalism. The hubris of the US neoconservative Midge Decter, speaking after the collapse of the Berlin Wall, sums it up well. “It’s time to say: we’ve won. Goodbye,” she stated grandly. Two conclusions were drawn from this perceived victory. One, that the model of unchained capitalism that had become dominant in the 1980s was the unimprovable end stage of human existence, boldly summed up by the US political scientist Francis Fukuyama’s book The End of History and the Last Man. Two, that the US and its allies now had unchecked power and could behave as the world’s police service. This was hubris, and inevitably, as anyone familiar with Greek tragedy knows, nemesis followed in its wake. The global power of the US had taken a severe hit in the 1970s, when its standing was weakened by the humiliating sight of panicked US officials clambering on to helicopters in Saigon, sealing a final defeat in Vietnam. But its main rival, the Soviet Union, proved to be in a far more parlous state, and its collapse offered the west a chance to resurrect itself, with the first Gulf war and armed interventions in former Yugoslavia offered up as vindication for “liberal interventionism”. Then came the horror of 9/11 – and the ensuing military adventures that resulted in human catastrophe as well as humiliating failure. War in Afghanistan descended into a bloody quagmire, with the Taliban ending the drawn-out conflict more dominant than they had been at the start. The invasion of Iraq would “open the gates of hell” in the Middle East, warned the Arab League secretary-general Amr Moussa – and so it proved. Nato intervention in Libya’s civil war ended in “victory”, as Gaddafi was toppled. But at what cost? Libya is now a war-ravaged failed state. It isn’t just western military invincibility that has been shattered by these various escapades. The contempt shown for international law set a precedent other states knew they could follow, encouraging global disorder. Research by Brown University suggests that about 4.5 million people died as a result of the post-9/11 wars. The mass death these ventures brought about, and the accompanying human rights abuses typified by Guantánamo and Abu Ghraib, have ignited a justified contempt for western claims to moral superiority. Some, like Vladimir Putin, have sought to use this contempt as ammunition for their own aggression. As well as its role in supporting Israel’s massacre in Gaza, the west must reflect on how it fostered the conditions in which a Putin-like figure could emerge in Russia. The Putin regime, of course, bears responsibility for Russia’s hideous invasion of Ukraine: the US isn’t the only powerful state capable of violence and destruction. But is there not more to the story? Does the neoliberal economic model that western states exported to Russia not share some of the blame? That Putinism exploited Russian despair after the cold war is incontrovertible; but so is the fact that western states promoted “economic shock therapy”. This triggered a more severe crisis than the Great Depression, roaring hyperinflation, a drastic fall in life expectancy, and oligarchs pilfering the nation’s wealth. Could a more stable, post-Soviet Russia have been inured from the revanchism of an authoritarian like Putin? This disastrous economic model not only destabilised Russia, but paid untold damage to western, liberal democracies too. Such unrestrained capitalism directly paved the way for the 2008 financial crash, from which the west never truly recovered. Many of its countries then embarked on a ruinous course of austerity, which led to stagnation and decline, the ideal conditions for a rightwing authoritarian surge. The subsequent rise of Donald Trump’s far-right movement now imperils the very future of US democracy. Everywhere, liberal democracy is in retreat, increasingly replaced by autocratic regimes such as in Hungary, which the European Union occasionally wrings its hands over but with little action to back it up. In most European countries the far right is surging, a worrying omen of the continent’s future. The triumphalism of western elites after the fall of the Berlin Wall was misplaced. Over three decades on, their hubris has proved disastrous, their wars and economic doctrine bringing blood, chaos and decline. Gaza is just the bloody culmination of the west’s loss of legitimacy. Much of the world already had disdain for its moral claims, but there is no turning back this time. The moral collapse is now complete, as much of the Middle East and beyond brims with contempt for Israel’s protectors. Things could have been different. There could have been accountability over previous foreign debacles: instead those responsible – from government ministers to hawkish newspaper commentators – walked from disaster to disaster, splattered with more and more blood, yet continued in their roles with their careers and reputations somehow intact. Meanwhile, rather than being treated with the respect those with insight deserve, the people who opposed these calamities at the time remain ostracised as fringe extremists or dupes of foreign enemies, despite being repeatedly vindicated. Just as we could have built an economic model that doesn’t hoover up wealth into the bank accounts of the tiny elite, the lessons of the west’s disastrous foreign policy history could have been heeded, and thus its catastrophic backing of Israel’s Gaza assault avoided. Alas, it was not to be. You may have found these last years of turmoil exhausting. Buckle up: the fall of the west has several more acts to come. Owen Jones is a Guardian columnist