In addition to a pandemic, this decade has already been overshadowed by the return of great power rivalries. Few developments could be more threatening to world peace. Three world wars—two of them hot, one cold—during the twentieth century highlighted the danger of high-stakes geopolitical competition.

To many observers, the era of great power rivalry appeared to end once and for all with the dissolution of the Soviet Union. But this assumption proved to be one of the gravest errors of the post-Cold War period (a time that abounded with momentous blunders and misconceptions). US political elites’ presumption of global empire—of a truly unilateral moment in world history—could not be sustained. Nor could the 'eternal peace' anticipated by Europeans following the 'end of History' in 1989, when Western liberal democracy and the market economy supposedly triumphed over all the alternatives.

On the contrary, the decades since the end of the Cold War have been marked by a loss of international order. As the last remaining global power, the United States exhausted itself in pointless wars in Mesopotamia and the Hindu Kush, and has since become increasingly self-absorbed.

The international system that America built after World War II began to disintegrate, leaving power vacuums that other powers—Russia, China, Turkey, Iran, and Saudi Arabia—sought to fill. Worse, the risk of nuclear proliferation suddenly returned to the fore as smaller regional powers began to pursue arsenals of their own.

Moreover, it was during the past decade that China emerged as a global power capable of challenging the incumbent hegemon. The new rivalry materialised fully following Donald Trump’s election to the US presidency in 2016. America started pursuing a narrowly nationalist agenda, and chaos within the global system increasingly emanated from the top.

Nowhere was the resulting power vacuum more palpable than in the Middle East. The US had ended its expensive and absurd war in Iraq and then gone on to defeat the Islamic State in Syria. Having become self-reliant in energy terms tapping domestic shale oil and gas, America set its sights on a fuller military withdrawal from the region. Iran, meanwhile, was standing ready to exploit the US departure. It soon ended up in an escalating struggle with Saudi Arabia, the Gulf emirates, and Israel for regional hegemony, fueling a horrific proxy war in Yemen.

In addition to openly signalling its intent to withdraw the US from the region, the Trump administration also abandoned America’s traditional role in the Israeli-Palestinian conflict. For decades, successive US administrations had pushed for a two-state solution and a fair compromise between Israel and the Palestinians, even while remaining wholly committed to protecting Israel. But the Trump administration backed Israel fully and unconditionally, creating the impression that the Palestinians no longer had any role to play.

The Trump administration’s approach to the issue, together with the danger emanating from Iran, did lead to the establishment of diplomatic relations between Israel and four Arab states, including two—the United Arab Emirates and Bahrain—in the Gulf. But with the latest armed confrontation between Hamas and Israel, the fantasy in which the Palestinians could simply be sidelined forever has been dispelled.

The latest conflict has included violent clashes on the Temple Mount around the al-Aqsa mosque, and, unlike in previous episodes, between Jewish and Arab citizens in mixed cities across the Israeli heartland. Four lessons should be drawn while the current cease-fire holds.

First, even if a two-state solution hardly seems realistic anymore, its political renunciation will lead more or less directly to a highly charged confrontation. Second, Palestinians and Arab Israelis will not simply stand by and allow themselves to be ignored in regional political settlements. Third, the Israeli occupation cannot be continued indefinitely. And, lastly, the US cannot simply abandon the region out of a lack of interest, at least not if it wants to maintain its role as the leading global power.

The return of the Israeli-Palestinian conflict has exposed the real distribution of power in the Middle East. Notwithstanding all of the changes of the past few decades, the fact remains that stability depends on the US. Though America no longer wishes to engage with the region, it has no choice but to keep doing so, lest a regional brushfire escalates into a global conflagration with nuclear risks.

In other words, the Middle East is proving to be this century’s Balkans. As in ex-Yugoslavia in the 1990s, America is the only global or regional power capable of guaranteeing regional peace—or at least of suppressing all-out war. Russia would like to assume this role, but it cannot. (It was able to intervene in Syria to the extent that it did only because the US refused to do so.)

As for China, it has no interest in assuming America’s Middle East role, nor could it do so if it wanted to. The Chinese regime simply does not have the mindset to become a guarantor of a global order far beyond its borders.

What about Europe? Although it would be one of the main victims of regional destabilisation, it is no longer a force to be reckoned with, and thus has reduced its involvement to that of providing financial resources in response to the latest crisis. Still, Europe plays an important supporting role.

Finally, among regional players, Turkey would like to step up, but it is hampered by its own weaknesses and the fraught history of the Ottoman Empire’s role in the Middle East. Iran and Saudi Arabia are confined to pursuing their own claims to hegemony within the Islamic world. And Israel is and will remain focused on its own defense.

That leaves only the US. Despite its past foreign-policy blunders, it is the only country with both the necessary political mindset and the technological, economic, and military power to exert a moderating influence in the region. The worst outcome for the international order would be a continuing US inclination toward self-isolation. Trump’s presidency already proved how dangerous that can be.

—Project Syndicate