Depending on which expert you ask, the "unipolar" world order, where America was the dominant superpower imposing its will and standards over the rest of the world, ended somewhere between the years 2000 to 2020. From the standpoint of military conflicts, the recently concluded Afghan war was the last war of the America-led unipolar world.
If you read human history over centuries prior to 1900, you would realise that the world was never unipolar, nor was it bi-polar. The world, rather, has always been multipolar -- where local hegemons shaped geopolitical affairs within their respective vicinities, with occasional, and often consequential, conflicts with newly arrived external forces, often resulting in historic realignments.
From that standard, both the unipolar world order after the collapse of the Soviet, and the bi-polar world order during the existence of the Soviets, were anomalies in our collective human experience.
After about seven decades of that anomaly, the world formally went back to its natural state – i.e., to a multipolar world order.
The multipolar world that is rapidly taking shape will be chaotic, just like the way the multipolar world that existed before was also chaotic.
The last 70 years of relative peace, which resulted in the biggest economic transformation involving the largest portion of mankind ever in history, was not peaceful for everyone, of course.
We had Vietnam, Rwanda, Bosnia, Iraq, Syria, Libya, and Afghanistan to name just a few of the major human tragedies. But to put things into perspective, there were no "Thirty Years' War", no "Hundred Years' war"; no world wars, and most importantly, no catastrophic wars among the "equals" i.e., direct conflicts involving the big powers during the unipolar world order.
All the global bodies and institutions created after the second world war that promoted multilateralism were essentially set up to mitigate big power conflicts. It was the presence of these institutions that never allowed the cold war between America and the Soviets to ever get hot.
The coming multipolar world order may bring back the naked, great-power rivalries and all the conflicts that come with it into the world stage.
The so called "big games" may re-emerge, so may the big theaters of war.
Therefore, it is extremely important for people from countries in the peripheries of the regional hegemons (like Bangladeshis) dispassionately understand the dynamics of the new multipolar world, play with the competing forces accordingly, and always try to side with the eventual winners, as opposed to being stuck with the losers of the next big games.
The first such required understanding is what brought the end of the unipolar order? The misguided war on terror is the most popular milestone and catalyst thought to be the force that had broken America's back.
Over extension is ultimately the time-tested folly of every empire. The War on Terror indeed extended America thin, and hollowed out the nationalistic zeal necessary for continuation of an America-led, militaristic unipolar world.
In fact, foreign wars, and unilateral American interventions became extremely unpopular over the last two decades in America -- enjoying near unanimous consensus even within America's fierce political divide.
More so than the War on Terror, and all the wastage and futility that came along with it, what necessitated the emergence of the multipolar world is ultimately changing economics of war and peace.
Due to the massive transfer of capital and knowledge from the West to the East, the center of gravity of global trade and commerce shifted towards the East over the last three decades.
When the current American century started back in the early 1900s, the size of the American economy was nearly half of the entire size of the global economy. America now constitutes only 15% of the global economy. As late as during the early 2000s, America was also the largest trading partner of most of the countries of the world - a status that is now enjoyed by China.
However, America losing out its relative competitive ranks to Asian economies, particularly the rapid emergence of an assertive China is only partially the reason that brought the America-led unipolar world to its end. The changing nature of commerce also played a role.
During the 1960s, America's largest and most profitable corporations were in energy, steel and chemical – industries that are otherwise known as the "War industries". Now, fast forward to 2020, America's largest corporations are Apple, Amazon, Microsoft, Google, and Facebook --- companies that provide services and products that are far more profitable during times of "peace."
The American economy today also produces more goods that are virtual, borderless, and transportable across the globe instantly. These are industries that are "globalist" in nature, and agnostic to the need of a unipolar world order.
America became a net exporter of hydrocarbons in 2012, exporting more American oil and gas than importing foreign ones. Starting from the 2030s, it is expected that the world of automobiles and several other key industries will move away from hydrocarbons altogether.
Such abruptly changing economic reality, along with America's fractured political climate, is forcing America to refocus its decades-old influence and alliances around the world, particularly in the Middle East, and look more inwards.
An inward-looking America, in turn, is going to expedite the multipolar world order, even if China were to falter economically or militarily down the road for whatever reason.
One key point to note here is that a multi-polar world does not necessarily mean a world with multiple, equally powerful players in global affairs. It is possible, and statistically most likely, that the multipolar world will continue to have one behemoth like America in the middle, whose military power will far outstrip the rest of the players.
No discussion about the future multipolar world order can finish without commenting on China.
Although there is a lot that is still in flux, China's role in a multipolar world may be less assertive and certain than what most Sinophiles currently want to portray.
Human potentials are often bounded by their histories. From that angle, the Chinese were never known to be hegemonic or imposing towards the outside world either due to capacity or character, or both.
China, therefore, may continue to prosper economically and militarily even further, but still fall short on its geopolitical achievements in a crowded field of over-imposing rivals in a multipolar world. The fact that there is near unanimous consensus among the world's largest democracies regarding taking a collective stance against China may make matters (in relation to world domination) quite tricky for the Chinese.
A totally re-shuffled, re-routed manufacturing supply chain away from China, amid increased automation, robotics and artificial intelligence, may make it possible, or even force China, just like America, to look inwards.