Vladimir Putin looked desperate on TV yesterday as he claimed that NatoThe North Atlantic Treaty Organisation was founded in 1949 to unite Western democracies in Europe and North America against the perceived growing threat of the USSR. It now has 31 members. was threatening Russia with nuclear weapons. "If the territorial integrity of our country is threatened," he said, "we will without question use all the means at our disposal... this is not a bluff."

Nato has made no such threat - and not even Ukraine has threatened to invade Russian territory. But his mention of nuclear weapons has alarmed many people. And the rest of his speech showed how he might find an excuse to use them.

Experts had wondered how he would react to Ukraine's dramatic success in recapturing territory.¹ "How does he escape the fate of the autocratA leader who rules by force and with absolute power, without the permission of others. who fails," asked William Hague in The Times, "that sudden demise when the army refuses orders, or the crowds stop being afraid?"

As many feared, he has raised the stakes.² In yesterday's speech, he announced a "partial mobilisation" of the armed forces. Three hundred thousand reservistsA member of a military reserve force. In peacetime, they have non-military jobs. would be immediately called up.

More worryingly, he announced that referendums would be held in Russian-occupied parts of Ukraine. People there will be asked whether they want to be part of Russia - and nobody doubts that the vote will be rigged to give the answer "yes".

Putin could then pretend that, by fighting for its own territory, Ukraine was attacking Russian soil - so he was entitled to use nuclear weapons in its "defence".

Both these moves might backfire. Observers believe that mobilisation is a sign of weakness, reflecting the heavy casualties Russia has suffered. While the KremlinThe official residence of the president of the Russian Federation, the Kremlin is used as a metonym for the government, in the same way as the White House and Downing Street refer to the US and UK governments. says that 5,937 soldiers have died, Western estimates put the dead and wounded at 80,000.

Throwing in extra forces could undermine support for the war in Russia, and make little difference on the battlefield. One expert, Mike Martin, argues in the Daily Telegraph that the new recruits would be badly trained and poorly equipped:

"Putin is sending these people to their deaths. The Ukrainian armed forces have killed tens of thousands of professional Russian soldiers with the best equipment that Russia could supply. What will they do with this mobilised reserve?"

As for using nuclear weapons, "This is the craziest option," according to William Hague. "It would unite the whole globe against Putin."

Yes: He has staked his political life on defeating Ukraine, so he will stop at nothing to achieve that goal. Since he does not care about other people, he is happy to risk any number of Russian lives.

No: He knows that even his own people would not support him if he provoked a nuclear confrontation. He relies on the leaders of the armed forces, who would almost certainly act to remove him from power.

Or... The conflict would not become a "world" war because no country would support Russia. Its allies would be afraid of becoming targets, while neutral countries would turn against it.