As we try to figure out what the next year holds in store for the world, one milestone looms menacingly on the horizon: The U.S. presidential election on Nov. 5.

The upcoming election will undoubtedly shape the history leading up to it and the history that follows. U.S. President Joe Biden, having restored respect for professional politicians through his experience and acumen, will seek a mandate to govern into his mid-80s. Some, even members of his own generation, wonder whether this is wise.

Meanwhile, Biden's likely opponent, former President Donald Trump, is just three years younger. Despite his age, numerous criminal indictments and refusal to accept the certified results of the 2020 election, Trump's grip on the Republican Party's base has enabled him to evade disqualification.

No U.S. presidential election in living memory has felt so consequential - and none has offered such uninspiring choices. In the run-up to the vote, politicians, pundits and corporate leaders will have to hedge their bets, because the uncertainty extends beyond the result to the question of whether the loser will accept defeat. A constitutional crisis is a real possibility.

The fate of leaders around the world hangs in the balance as well. Ukrainian President Volodymyr Zelenskyy, struggling to lead his country following nearly two years of bloody war, will be praying for Biden's victory, while Russian President Vladimir Putin will be hoping just as fervently for Trump. Remarkably, Putin's best hope for victory in his war on Ukraine might be the election of a Republican U.S. president. Nevertheless, whoever wins in 2024 will become the steward of a world in flames, from Gaza to Crimea.

The global significance of this U.S. election suggests that predictions of the United States' decline might have been premature. It is still a colossus dominating the global stage, outspending rivals on defense and leading a vast system of alliances.

As home to the world's most advanced universities and research centers, the U.S. holds an effective monopoly on many cutting-edge technologies, especially artificial intelligence. Its new industrial strategy, which adapts mercantilist economics to the 21st century, shows the lengths it will go to maintain its competitive edge. Confronted with the challenge of a rising China, America has shown it can foster alliances between erstwhile rivals like Japan and South Korea and implement a "small yard, high fence" policy to keep China from stealing key technologies and high-value knowledge.

Lax Americana

Despite all this, U.S. allies have good reason to doubt America's stability and staying power. As a hegemon, it tends to waver: Former President Barack Obama failed to stop the Syrian regime from gassing its own people, and Biden abruptly abandoned the Afghans to the Taliban early in his tenure. Even in regions where the U.S. remains engaged, like the Middle East, America's grand designs have been met with frustration. Just recently, Hamas, Hezbollah, and Iran have demonstrated their disruptive capabilities when they sabotaged, or at the very least delayed, success for the American effort to secure a historic rapprochement between Israel and Saudi Arabia.

America's domestic politics has long perplexed its allies, but its polarized dysfunction can no longer be borne lightly, as partisan feuding hobbles American power overseas. The pathologies of the U.S. political system, frozen in time by an effectively unamendable constitution and riven by regional, class, and racial cleavages, make it impossible for America's allies to predict how these domestic political conflicts will affect U.S. foreign policy. These internal divisions may even leave the U.S. as fatally distracted as Israel's did before the Oct. 7 Hamas attack.

When a handful of Republican hard-liners in the House of Representatives can put essential military funding for Ukraine at risk, no ally can be sure of America's long-term commitment to the war with Russia. As the Stanford University historian Stephen Kotkin has warned, all Russia needs to do to upend the 2024 U.S. election is to launch a surprise attack, as the North Vietnamese did with the 1968 Tet Offensive.

Amid the chaos of an election year, congressional support for Ukraine might increase, but then again, it might crumble, much like U.S. resolve in Vietnam did in 1968. This would jeopardize the more than $1 billion a month in financial and military aid that Ukraine needs to maintain its current position on the battlefield. If Congress buckles, U.S. support dries up, and Ukraine is forced to seek peace, the next U.S. president would face a Chinese-Russian alliance that has managed to redraw European land borders by force.

Transatlantic tremors

The Europeans, on their own, cannot step into the breach if the U.S. fails them. They are nowhere close to achieving the "strategic autonomy" that French President Emmanuel Macron believes Europe needs to defend itself. Should U.S. support for Ukraine falter, either because Biden fails to secure aid through Congress or because a re-elected Trump abandons Ukraine and forces Zelenskyy to accept defeat, NATO's survival might be called into question.

A Carthaginian peace that turns Ukraine into a rump state and leaves it at the perpetual mercy of renewed Russian aggression would represent more than just a defeat for Ukraine, America, and NATO. It would herald a grim future for the entire European continent, which for the first time might find itself subordinate to a triumphant Russo-Chinese sphere of influence in Eurasia.

This would be the worst possible outcome of the 2024 election. But it's a scenario that can still be averted if Americans on both sides of the political divide remember why European security remains a vital national interest. At the same time, Europeans must stop free-riding on American security guarantees and invest in building their own military capabilities. The fact that Ukraine's fate could determine the future of Europe as a whole should keep allies on both sides of the Atlantic focused and united.

But even if Ukraine survives and prevails, the next U.S. president will inherit an international order in ruins. While the West views Russia as a rogue state, the fact that 35 countries abstained and five voted against the October 2022 United Nations General Assembly resolution condemning its invasion of Ukraine suggests that a cornerstone of the international order - the U.N. Charter's prohibition on using force to alter borders - is giving way.

No world order

Historically, newly independent countries have been ardent champions of national sovereignty. But now, emerging powers like Brazil, South Africa and India have maintained a self-interested and cynical neutrality as Russia, Europe's last empire, tries to destroy a sovereign state.

This shift represents something less hopeful than the mere maturation of the so-called Global South and its desire to break free of American hegemonic control. We are living through the unraveling of the international system created in the aftermath of World War II. In this emerging world, Anne Applebaum notes, "There are no rules."

The pillars of the post-WWII international system - the U.N. Charter, the Universal Declaration of Human Rights and the Geneva Conventions - have been ignored more than they have been upheld over the decades. Nonetheless, they established standards that acted as a brake on states' conduct and created norms that encouraged most countries to value their moral standing, as a decent reputation was understood to be a critical lever of soft power.

The haunting sight of the bodies of dead civilians left behind on the streets of Bucha after Russia's withdrawal has underscored the wanton cruelty of a permanent member of the U.N. Security Council that no longer cares what the world thinks. Similarly, the harrowing images of Israelis massacred in kibbutzim and at a music festival near the Gaza border have given us a glimpse of a world where no rules restrain combatants, where state deterrence fails, where desperation fuels terror, and where countries like Iran and Qatar lack the ability or the will to restrain their proxies.

The foundations of the international order cannot be rebuilt in a year or even a decade. The world's countries may need to live through a period of anarchy to rediscover the virtues of the order they have abandoned. Positive change hinges on major powers realizing that their interests lie in maintaining stability rather than undermining their adversaries. A shattered global system rewards bad behavior. Without significant incentives to cooperate or curb their worst instincts, large and small countries alike jostle for leverage and influence.

A generation's last gasp

The 2024 election is shaping up to be a contest between a man who understands the value of the international order established in 1945 and aims to rebuild it, and one who does not care whether it burns to the ground. While the U.S. has long been torn between internationalism and noninterference, never before has American isolationism had such a wanton or dangerous tribune as Trump. This alone underscores the election's existential importance for the rest of the world.

It will also likely be the last U.S. presidential election featuring two candidates who came of age in postwar America, a generation that prospered during the Cold War and reveled in the post-1989 euphoria, only to be jolted by the 9/11 attacks and the 20 years of war, economic dislocation, and rising inequality that followed. Beyond the collapse of the international order, they leave the next generation with a mountain of unsolved problems such as climate change, unchecked AI, pandemics and deep democratic dysfunction. The geriatric options on the ballot in November are a crushing indictment of a generation that has clung to power for too long and failed the crucial leadership test of preparing for its successors.

Any thoughtful person is bound to be worried. But worry need not lead to despair. Hope depends, as it always does, on human virtues like wisdom, restraint, humility, and patience. To restore optimism in the coming year, several conditions must be met: The U.S. must stay the course in Ukraine, which must repel the Russian invaders; Israel must crush Hamas without falling into the trap of reoccupying Gaza; Europe must commit to self-defense; China must edge away from its flailing Russian client state; and rising powers like India, Brazil, and South Africa must abandon moral equivocation.

The rest of us observant and engaged citizens must reaffirm our faith in human agency. Individuals do matter. We are not pawns in some great historical chess match. The leadership choices we make can shape the lives of millions for better or worse. As U.S. citizens head to the polls next November, their votes could alter the course of history. We can only hope they choose wisely.

From Project Syndicate