No sanctions — not even the most stringent currently under discussion — can avert this outcome, any more than sanctions reversed the Iranian Revolution or forced the Soviets out of Afghanistan in 1979-80. In that sense, the current debate about the SWIFT global messaging and payment system is really a distraction. No amount of financial pain, whether it is inflicted on Putin personally, the Russian banks, the Russian central bank or the entire Russian population, can stop the bombardment of Kyiv. Even a ban on Western imports of Russian oil and natural gas — which remains highly unlikely, given the difficulty and cost of swiftly replacing those source of energy — would not deter Putin from pursuing his war by all means necessary to secure victory.

Putin is a student of history. He knows the fate that awaits Russian leaders who lose wars. We all recall what befell the last Romanov tsar, Nicholas II, who not only suffered defeat in World War I, but also lost the Russo-Japanese War in 1905, a defeat that triggered the first of two Russian Revolutions.

But another sobering case that Putin must ponder is the wretched fate of Nicholas I, who went to war with the Ottoman Empire in 1853 only to find Russia isolated and faced with an Anglo-French expedition to Crimea that culminated in the fall of Sevastopol. Though he died of pneumonia in 1855, it was said that the tsar refused treatment as the ignominy of losing the Crimean War was intolerable to him. 

Eoin Treacy's view

The gamble of starting any war is you risk losing more than you gain. Russia’s best hope is for a neutral Ukraine with an administration that is reasonably friendly to Moscow. If the blitzkrieg approach does not work, a protracted messy Chechnya-style ground offensive is hardly likely to create the lasting solution he seeks.

Both Georgia and Chechnya are far away from the EU’s heartland. Ukraine is next door. There will be a steady supply weaponry to fuel a guerrilla war in Ukraine for as long as it is required. It is entirely possible Putin will not survive long enough to see victory, however pyrrhic.