He must accept defeat unless Russian forces invade Ukraine.
The world faces a moment of maximum danger in Ukraine. Vladimir Putin has perhaps just a few days to decide whether to launch a full invasion of the Donbass, or accept defeat and let the Ukrainian military crush his proxy forces.
Nato officials say Russia has massed 20,000 troops in battle-readiness near the border, backed by Spetsnaz commandos, tanks and aircraft. Vehicles have been marked with peace-keeper labels already. Nato sees every sign that the Kremlin intends to disguise an attack as a "humanitarian mission".
This is more serious than the Russian invasion of Afghanistan in 1980. That was a "colonial war". The Soviet Union was a careful, status quo power in its final decades. It held captive nations but did not overrun new borders in Europe. Putin is expansionist, and far less predictable. He is, in any case, captive to the chauvinist fever that he has so successfully stoked.
He has been clear from the outset that he will deploy any means necessary to bring Ukraine back into Russia's orbit. Only war can now achieve this, since all else has failed, and since he has turned a friendly Ukraine into an enemy by his actions. The awful implications of this are at last starting to hit the markets.
"People thought that Russia was just playing a game of brinkmanship, and that pragmatism would prevail in the end. There is real fear now that this will spin out of control," said Chris Weafer, from Macro Advisory in Moscow.
Yields on 10-year rouble bonds have jumped to 9.7 per cent, up 130 basis points since June. A liquidity crunch is rapidly taking hold across the financial system.
"The market is shut. Not a single Russian entity has been able to borrow anything in dollars, euro or yen since early July," Weafer said.
The Kremlin's gamble has gone horribly wrong. The eastern regions of Ukraine have failed to rise in mass support for Putin's front organisations, led by political operatives from Moscow, and patently run by the Russian security apparatus (FSB/GRU) as even Russian newspapers admit. The latest report by the United Nations accuses these units of "egregious abuses", carrying out systematic intimidation through torture and execution.
Putin has failed equally to drive a wedge between America and Europe, or to paralyse the EU by playing off one country against another. Germany has not cut a special deal, though its 6000 companies in Russia are on the frontline. It has gone beyond the EU measures, blocking a 100 million ($160 million) export of combat training kit by Rheinmetall.
Cyprus, Bulgaria, Hungary and Austria quietly toed the EU line on sanctions. None dared to veto measures that shut Russia's banks out of global finance, and that block technology needed to open up Russia's oil and gas fields in the Arctic or the shale reserves of the Bazhenov Basin.
President Barack Obama's slow, methodical escalation suits the complicated chemistry of Europe, the region that will pay the economic price. There would have been a transatlantic crisis if the hotheads in Washington had prevailed.
Putin now faces draconian sanctions from the US, EU, Japan, Canada and Australia together. He can strike back by asymmetric means - perhaps a cyberattack - but tit-for-tat retaliation can achieve nothing. There is no equivalence. Russia's economy is no bigger than California's. This is an economic showdown between a US$40 trillion power structure, and a US$2 trillion producer of raw materials that has hollowed out its industrial core. The new arsenal of sanctions refined by a cell at the US Treasury - already used with crisp effect against nine countries - is nothing like the blunt toolkit of the 1980s or 1990s. Nor can Russia retreat into Soviet self-sufficiency. It is locked into global finance. The International Energy Agency says Russia needs to invest US$100 billion ($118 billion) a year for two decades just to stop its oil and gas output declining.
Russian companies and state bodies owe US$610 billion in foreign currencies. They must repay US$84 billion by the end of the year, and US$10 billion a month thereafter. There is no immediate crisis. Russian companies have US$130 billion of cash holdings. The central bank has promised to deploy its US$470 billion of foreign reserves as a second line of defence. Russia can muddle through for a while, depending on the pace of capital flight. At best it is slow suffocation.
European officials calculate that Putin will not dare to cut off energy supplies, since to do so would bring the Russian state to its knees within months. But even if he tried - as a shock tactic - it would not achieve much. Oil can be obtained anywhere.
Europe's gas inventories have risen to 81 per cent of capacity, up from 46 per cent in March. Britain is at 94 per cent. There is a sudden glut of liquefied natural gas in Asia that has caused prices to fall from more than US$20 per million BTU earlier this year to US$10.50. The LNG is being diverted to Europe, landing in Britain at just US$6.50.
Japan has just given the go-ahead for two nuclear reactors to restart in October, with seven likely by the end of the year. Koreans are also firing up closed nuclear reactors. All this frees up LNG.
Whether this is fruit of a co-ordinated strategy, the net effect is that inventories and spare LNG could cover a Russian cut-off for a long time, probably through the winter with rationing. Areas of eastern Europe have no pipeline supply from the West, but "re-gas" ships could plug some gaps in an emergency. The gas weapon is not what it seems.
The Kremlin is counting on acquiescence from the Brics quintet as it confronts the West, and counting on capital from China to offset the loss of Western money. This is a pipedream. China's Xi Jinping drove a brutal bargain in May on a future Gazprom pipeline, securing a price near US$350 per 1000 cubic metres that is barely above Russia's production costs.
The two countries are rivals in central Asia, where China is systematically building pipelines that break Russia's stranglehold. China has large territorial claims on Far Eastern Russia, land seized from the Qing Dynasty in the 19th century.
Even if Putin's strategy of a Euro-Asia alliance with China succeeds, it will reduce Russia to a vassal state of China, a supplier of commodities with a development model that dooms it to backwardness.
"It is a dangerous illusion. We are witnessing the funeral of Russia," said Aleksandr Kokh, a former top Kremlin official.
Putin is stuck in a Cold War timewarp, deaf to the shifts in world power. He has been obsessed with an imaginary threat from an ageing, pacifist Europe in slow decline, turning manageable differences into needless conflict.
Yet at the same time he is throwing his country at the feet of a rising power that poses a far greater threat in the end.
Putin has misjudged everything. He has decisive force only on the east of Europe's battlefield. Ukraine is not a member of Nato.
The West has stated that it will not deploy forces if it is invaded. Novorossiya is his for the taking. It is his last lethal card.
Russia retaliates over sanctions
Russian President Vladimir Putin has hit back against countries that have imposed sanctions over the Ukraine crisis, ordering trade cuts that an official said would include a ban on all imports of agricultural products from the United States.
The full list of products to be banned or limited for up to one year is to be published today.
But the state news agency RIA Novosti quoted Alexei Alexeenko of Russia's plant and veterinary oversight service as saying "from the USA, all products that are produced there and brought to Russia will be prohibited".
Alexeenko also was quoted as saying he thinks all fruits and vegetables from European Union countries will also be banned.
The move follows the latest round of sanctions against Russia imposed by the EU last week, which for the first time targeted entire sectors of the Russian economy.
President Barack Obama said in a news conference yesterday that US sanctions against Russia over its actions in Ukraine are straining the Russian economy.
The US and the EU have accused Russia, which annexed Ukraine's Crimean Peninsula in March, of fomenting tensions in eastern Ukraine by supplying arms and expertise to a pro-Moscow insurgency, and have imposed asset freezes and loan bans on a score of individuals and companies.
White House spokeswoman Laura Lucas Magnuson decried the move, saying: "Retaliating against Western companies or countries will deepen Russia's international isolation