September 1, 1939, has gone down in history as the day the Second World War began. The Wehrmacht invaded Poland, and two days later Britain and France declared war on Germany. Except that the reality was much more complex.

The war that ultimately devastated almost the entire planet did not emerge in a single morning. It had begun taking shape years earlier, through a series of seemingly peripheral conflicts: the Japanese invasion of Manchuria in 1931, the Italian attack on Ethiopia, the Spanish Civil War, and Nazi Germany’s expansionist policy in Central Europe.

For a long time, each crisis was treated as a separate matter. Until it stopped being one.

That is precisely the most alarming element of today’s international situation. From Ukraine to the Middle East and from Taiwan to the Korean Peninsula, wars, military alliances, and economic conflicts are no longer developing “in vitro.” They appear to be converging, and four years after Russia’s invasion of Ukraine, the question is no longer merely whether the world could be led into a broader conflict. It is whether the first pieces of such a conflict are already in front of us.

A global conflict does not have to start all at once

In 2022, there was concern that Ukraine could become the France of 1940: a country that would collapse within weeks against a numerically and militarily stronger adversary. That did not happen. Ukraine proved far more resilient than the Kremlin had anticipated and far more adaptable than several Western governments expected. Russia did not capture Kyiv. Volodymyr Zelenskyy did not leave the country. The Ukrainian Armed Forces did not collapse. Above all, however, Ukraine transformed the war into a vast laboratory for 21st-century military technology.

Low-cost drones, artificial intelligence, electronic-warfare systems, and strikes hundreds or even thousands of kilometers from the front have changed, at unprecedented speed, the way a modern conflict is waged. The worrying thing is that the war did not remain contained. Quite the opposite. It began connecting with others.

Russia is expanding pressure on Moldova and European countries, while threats from Moscow of even the use of nuclear weapons are now being heard almost systematically. At the same time, Hamas’s 2023 attack on Israel gradually evolved into a much broader regional conflict. Israel and Hezbollah. The Houthis in the Red Sea. Iran. The United States. The Gulf states. And now even the two major fronts, Ukraine and the Middle East, intersect.

Ukraine has carried out strikes in the Caspian region aimed at disrupting the transfer of Iranian military equipment to Russia. Every interceptor missile used in the Middle East is a missile that cannot be sent to Ukraine. One war is now beginning to determine the capabilities of the other.

From “partnerships” to a real axis

The second major element is that the countries challenging the Western international order are no longer limiting themselves to diplomatic handshakes and joint statements. They are cooperating operationally. North Korea has supplied Russia with millions of artillery shells and has sent personnel to support Russian operations. In return, Moscow is providing Pyongyang with know-how that can be used to modernize the North Korean Armed Forces. China is the critical supplier of electronic components and dual-use technologies that enable Russia’s military industry to continue producing drones and other weapons systems. Iran has supplied Russia with technology and equipment used on the Ukrainian front.

Moscow, for its part, has every reason to reciprocate by providing intelligence, know-how, and military support to its partners. This is now something much more than a loose “axis of authoritarian states.” It is a system of exchanges. One has ammunition. The second has electronics. The third has drones. The fourth has intelligence and military know-how. And this structure becomes even more significant if the next major front opens in the Pacific. In a possible Chinese operation against Taiwan, Russia’s contribution would not necessarily take the form of ground troops. It could involve intelligence, raw materials, missile technology, or even Russia’s Pacific submarine force. And then the West would face not one crisis, but several simultaneously.

The West’s problem lies within the West

Here perhaps lies the greatest similarity with the 1930s. The adversaries know what they want more clearly than Western democracies know what they are willing to defend. Washington accuses its allies of not spending enough on their defense. The allies accuse Donald Trump of treating alliances more as commercial transactions than as strategic instruments of power. Both sides have arguments. Europe and Canada spent decades investing inadequately in defense, relying on American military power. But at the same time, the trade conflicts Washington is opening even with close allies undermine precisely the advantage that neither China nor Russia possesses: a global network of alliances.

When the US clashes economically with Canada, or when European governments begin wondering whether they can take American security guarantees for granted, the result is not simply a trade dispute. It is strategic erosion.

Wars are emptying the stockpiles

The fourth warning sign is more material and less theoretical. The Western world is discovering that over the past thirty years it has not built the industrial base required for a major and prolonged war. Ukraine showed this first. The Middle East confirmed it. Interceptor missiles, artillery shells, air-defense systems, spare parts, and shipbuilding capacity cannot be produced overnight. The United States has the most powerful military in the world. But that does not mean it possesses inexhaustible quantities of ammunition.

Nor does it mean that the model on which American military superiority was built over the past decades remains intact. In Ukraine, extremely expensive armored vehicles and other systems designed for 20th-century warfare are being forced to hide from drones that cost a tiny fraction of their value. Technology is changing faster than military doctrines. At the same time, the months-long deployment of the aircraft carrier USS “Abraham Lincoln” and the difficulties of supplying it highlighted a deeper American problem: the fleet is historically small, and the shipbuilding industry is struggling to build and maintain vessels at the pace that a major confrontation would require. In a multi-front war, the mathematics become unforgiving.

And what if the next crisis is not military?

There is also a fifth factor that could act as an accelerator for all the preceding ones. The economy. The major difference from the 1930s is obvious: the world today is not in a global depression. But that does not mean the economic foundation is stable. The explosion of investment in artificial intelligence has created enormous valuations and expectations. The question is what will happen if some of those expectations prove excessive, as happened with the internet bubble at the beginning of the century. At the same time, US government debt is approaching levels that make even small increases in borrowing costs extremely expensive. A crisis in the US Treasury market, a deep recession, or major turmoil in Japan could transmit enormous pressures throughout the international financial system. And then the geopolitical equation changes dramatically.

During periods of economic crisis, democracies tend to become more inward-looking. Societies demand less spending abroad. Governments fear the political cost of military operations. Authoritarian regimes, by contrast, can view such a period as a window of opportunity.

The war no one will declare

This is ultimately the dangerous mistake when we discuss a possible Third World War. We imagine it like the Second. An invasion. A declaration of war. A date that will be written into the history books by the historian of the future. The next world war, however, may not begin that way. It may begin with a war in Europe. Continue with a conflict in the Middle East. Expand with a crisis around Taiwan.

It may be connected by Russian weapons, North Korean ammunition, Chinese electronics, and Iranian drones. And facing them may be a West that still possesses enormous economic and military power, but struggles to decide how much of it it is actually willing to use. That is precisely what happened during the interwar period. The individual crises seemed manageable for years. Until they converged. And by then it was already too late for them to remain peripheral.