Russia’s bold actions in Crimea and China’s continuing expansion in the South and East China Seas mark the return of great-power politics. We should not be surprised. Although many Americans thought it did, great-power politics never went away. This is because humans never went away: The world may change, but humans do not.

While there is considerable surprise and anger in the West, the actions of China to push the United States out of the South China Sea or Putin’s seizure of Crimea reminds us of a fundamental truth. Power is the coin of the realm in international politics. States want power. But this desire does not arise out of a vacuum. States want power because men want power—a feature of biological organisms stretching back to the origin of life on Earth. Evidence of this is so woven into the fabric of economic, social, and political life that we rarely question or notice it.

The behaviour we expect—indeed praise—in business is also true of international politics. Firms strive for more profit, market share, and return to investors. In essence, they try to maximize their power, all the while undermining or preventing competition.

Athletes do the same. We praise rather than condemn Peyton Manning or Albert Pujols for trying to be his best in a fiercely competitive and dangerous environment.

Domestic politics is often described as a “contact sport,” and not for the timid. Bold action is rewarded. Bill Clinton, Dick Cheney, or Barack Obama did not rise to their heights by being shrinking violets.

What is true for business, sports and domestic politics is true for international politics.

It is just much worse.

Corporate leaders are praised, but Putin is condemned for the same type of behaviour, albeit in a crucially different realm.

Unlike business, baseball, or domestic politics, the realm of international politics is the realm of anarchy. There is no world government and so actions, like preying upon another state, can go unpunished. Power, therefore, reigns supreme.

The cause of power seeking behaviour is broader than Vladimir Putin or Xi Jinping, or modern Russia or China. It is to be found in evolution.

Evolution has four insights that can help us understand Beijing’s and Moscow’s actions.

First, Americans should recognize that leaders are not “normal” people. . As social mammals, those topping the hierarchy differ in important ways from those at the bottom. Leaders demonstrate certain, similar behaviors that are over-represented among those who rise to the top. Some of these are positive. Decisiveness, for example, is the core of leadership. But many are negative, such as the arrogance and abuse of subordinates—the so-called “toxic boss.” It is not that leaders are from Mars and followers from Venus. Leaders are as focused and ruthless as House of Cards while the rest of us are tuned into The Daily Show. Their brains are different from the rest of us.

Second, evolution explains why leaders will have a tendency to possess positive images of themselves. Fortune favors the bold, and this contributes to their overconfidence and the illusion that they are in control of the situation. As a result, they have a proclivity to take bold action, even somewhat regardless of the risks and costs. Sometimes that can be offset by calmer voices or bureaucratic lethargy, but not always. And sometimes it works, as Putin demonstrated in Crimea, and as China is doing in the East and South China Seas. Boldness pays when others can only bluff.

Third, evolution and Machiavelli overlap in the recognition that leaders want power to work their will despite opposition: in sum, dominance. Power provides all of the benefits that accrue to rulers, from money, to aid to family, friends, and supporters, to privileged access to mates—power is the ultimate aphrodisiac, as Kissinger once wrote. And once they have it, they are loathe to give it up, not just to lose its trappings and other benefits, but for the loss of dominance itself. Power has been shown to stimulate reward circuits in the brain, driving leaders to seek even further exploits.

Fourth, evolution leads to flexible, contingent strategies. Leaders will not be naturally cooperative or naturally aggressive at all times in all circumstances, rather these behaviors will be activated and exaggerated in certain settings. Part of the problem the United States faces with China and Russia is that each increment of power allows these leaders to visualize and realize greater ambitions, especially if they are not challenged. Cooperation can work well in achieving ends, but aggression can be even better or cheaper.

The application of evolution to the study of political behaviour is relatively new, but it offers a variety of novel insights into the causes of that behaviour. Whether we like it or not, evolution’s stamp on human thought and behavior is significant. Exploring its impact does nothing to legitimize Putin’s actions, of course, but it does help us to understand them.

Finally, Americans should recognize that the behaviour of these men is not an aberration. It is in accord with the types of behaviour we have seen throughout history, and that in the future we should expect, prepare to deter and, if necessary, contain. Power is ingrained in our psyche not by accident or mistake, but rather because it is a vital ingredient of survival.

Dominic Johnson is Alistair Buchan Professor of International Relations at Oxford University and Fellow of St. Antony’s College. Bradley A. Thayer is Reader of International Politics, University of Bath.

Image: Wikimedia Commons/Yathin S Krishnappa. CC BY-SA 3.0.