Illustration: Pat Campbell

Illustration: Pat Campbell

Let us conduct two thought experiments. First, hard as it is, let's imagine Vladimir Putin is a committed democrat and Russia is a fully consolidated democracy. Given its history and geopolitics, the place of Kiev in Russia's cultural and national identity, and Crimea's strategic importance for Russia's security, would a democratic Putin and Russia have reacted differently to the challenge to core interests posed by Ukrainian developments? Not a chance.

Now imagine - this is less hard - that instead of the wimp Barack Obama, as caricatured by the testosterone-fuelled right-wing American hawks, the US president was Ronald Reagan or Richard Nixon. Could they have confronted a heavily nuclear-armed Russia's move to retake Crimea (''gifted'' to Ukraine by Nikita Khrushchev in 1954) any differently? Nyet, nada, not a chance.

Whatever happens, this is not the West's fight to lose. We should take a deep breath and calm down. The crisis is a perfect illustration of Thucydides' dictum: The strong do what they can, the weak suffer what they must.

It does not portend a new Cold War. There is zero prospect of Russia re-emerging as a global military challenger to the US any time soon, of posing an ideological challenge to democracy, or resurrecting the command model of socialist economics to challenge today's dominant market principles.

In terms of classical realism and balance of power, Ukraine's actions were dangerously provocative to its great power neighbour; Russia's reactions were entirely predictable in its core sphere of influence; and America's impotence neither reflects its true power nor is an authentic test of credibility or will to act when its vital interests are under threat. Harvard University's Stephen Walt writes: ''Tough-minded realism is a better guide to foreign policy than liberal idealism or neoconservative bluster.''

Russia is a traditional European great power comprehensively defeated in the Cold War. The West behaved towards it as if it had been militarily defeated and conquered. Instead, it reacts like a wounded great power when NATO expands its borders to the limits of Russia's territory, betraying Moscow's understandings of the terms of its acquiescence to Cold War defeat.

Putin has described the dissolution of the Soviet Union as the last century's greatest geopolitical disaster. We rubbed its nose repeatedly in the dirt of its historic Cold War defeat, blind to - nay, disdainful of - its interests and complaints. Now we are surprised it carries resentment and reacts like a great power when we engineer a coup in its front garden to oust a democratically elected leader because he is pro-Russian?

Of course great powers can no longer ride roughshod over other countries' sovereign rights. A robust norm exists against aggression. Kofi Annan warned Washington in 2003 that the illegal Iraq invasion risked opening the Pandora's box of unilateral aggressions. Some of us warned in these very pages the war on Iraq risked moving the world from the rule of law to the law of the jungle.

John Kerry declares in the 21st century you cannot just invade countries on a ''completely trumped-up pretext''. This from the Secretary of State of a country that did exactly that without the excuse of vital security interests being under threat to a country on the other side of the world; and from a man who voted for that war (having voted against the fully justified Gulf War I and who described the military coup in Egypt as a restoration of democracy. So much for satire.) When Washington and London warn that acts of aggression have costs and consequences, they should first hold a mirror to the recent history of their own countries: self-parody trumps self-righteousness.

After the Cold War, Europe insisted on the right of Yugoslavia's provinces to self-determination. When Kosovo, part of Serbia since the Middle Ages, wanted to secede, NATO bombed Belgrade into submission. Crimea was part of Russia since the reign of Catherine the Great. By the logic of the Balkans in the 1990s, if Ukraine resists Crimea's wish to reunite with Russia, NATO should be bombing Kiev into submission? Or perhaps Putin should go one better than an op-ed in The New York Times and quote Shakespeare's Shylock to Obama: ''The villainy you teach me, I will execute; and it shall go hard but I will better the instruction.''

Threats of sanctions are also curious. Economic exchanges with Russia are not acts of charity but reflect market efficiency. Sanctions will introduce distortions and impose costs on us also. How does it profit us to suspend collaboration with Russia in jointly guarding the vessel that destroys Syria's deadly chemical arsenal? ''There is a pleasure sure in being mad, which none but madmen know.''

The test of policy is not how it starts but how it all ends, Henry Kissinger reminds us. The most critical factor for the Asia-Pacific region is what lessons China reads into all this. It has already given hints that going by US precedents, a first-rate power uses international law to enforce compliance on others but dismisses legal restrictions on its own behaviour. The West has lost the capacity to lay down the law to all others, flout global rules whenever it suits it, and dare everyone else to notice. More and more do. The sooner we return to the belief that the world is better if all countries, even great powers, must be subject to the rule of international law, the better.

Meanwhile, in Ukraine, all parties should heed Kissinger's sage advice. Neither side domestically or externally should seek to dominate the other faction, but act on historical perspective and strategic logic to compromise, share power, and let Ukraine be a bridge between two worlds. Just let it be.

Ramesh Thakur is professor in the Crawford School of Public Policy, Australian National University.