When Vladmir Putin rolled the dice of war just over a month ago, he was not alone in thinking that his imperial enterprise was a dead cert. More than a few senior figures in the British and other western governments shared his assumption that Russian forces possessed the numerical and technological superiority to prevail, and swiftly. It was widely thought that by now we would be looking at a subjugated Ukraine while a triumphant Putin taunted the west to do anything about it. Belligerent autocrats the world over would have been encouraged to believe that tomorrow belongs to dictatorships and the liberal democracies would never have looked so feeble. The decline of the west would no longer be a contentious draft of the history of the early 21st century. It would be more like a bitter fact. So when the leaders of Nato, the EU and the G7 recently gathered in Brussels, one of the strongest emotions was sheer relief that the Russian invasion has not gone to Putin’s plan. Only a minority of the credit for that belongs to western leaders, too many of whom were slow to supply the Ukrainians with the means to defend themselves and some of whom are still not rising to the gravity of the moment. The failure of Putin’s gamble is down to Russian military incompetence making contact with heroic, fierce and skilful Ukrainian resistance. In the early days of the conflict, the White House thought it so unlikely that Volodymyr Zelenskiy’s government could survive that it offered an escape route to save him from capture by the Russians. His response was the magnificently scornful “I need ammunition, not a ride”. The inspirational example of the Ukrainian leader and his defiant people has played a vital role in rallying and unifying the west. Another big factor is guilt. There is necessary shame among the democracies that Putin was emboldened to invade by the puny responses to his earlier aggressions. It wasn’t wrong to encourage Ukraine’s aspirations to join Nato. The mistake was not to satisfy them. That left Ukraine stranded in a dangerously ambiguous place, called “one of us” by the west but denied the protection of Nato’s nuclear umbrella, an exposed position that did not contain Russian aggression but amplified it. Along with the spasms of guilt and gasps of relief, there is also self-congratulation in western capitals that the democracies are displaying a resolve many doubted they could muster. Nato’s eastern flank is being reinforced. Finland and Sweden are debating whether to join the alliance, a window of opportunity they might be wise to leap through while Putin is preoccupied. Georgia and Moldova have applied to join the EU, which has managed to park some of its internal quarrels to concentrate on the external threat. The Swiss have put aside their neutrality to join the freezing of Russian assets. Even the ineffable silliness of Boris Johnson, who just couldn’t stop himself making a tasteless and ludicrous comparison between Brexit and Ukraine’s mortal struggle for freedom, hasn’t spoilt the mood. The most remarkable sight has been to witness Germany waking from its long slumber. During the Nato operation to prevent ethnic cleansing by the Serbian dictator Slobodan Milošević in the late 1990s, Gerhard Schröder told Tony Blair that Germany would never participate in military action because his country had become “essentially pacifist”. No longer. Under Olaf Scholz, Europe’s mightiest economic power has committed itself to a huge programme of rearmament – and pollsters report that three-quarters of the German public embrace the ambition. Yet question marks still hover over the democracies and their commitment to ensuring that Putin is defeated. The most pressing is about the scope and scale of the resources that Nato is prepared to commit to the defence of freedom. On this subject, President Zelenskiy is too eloquent for the comfort of many western leaders. When he addressed the Nato summit, he made a characteristically passionate appeal for “military assistance – without restrictions”, asking for the alliance to supply a tiny fraction of its military hardware: “You can give us 1% of your planes, 1% of your tanks.” This tugged on a significant rift between Nato members and within Nato governments. Some, notably the Americans and the French, are happy for the Ukrainians to receive defensive weaponry, such as anti-tank and anti-aircraft missiles, but balk at warplanes and armour. They fear travelling a road that might lead towards escalation and even Armageddon. Sources report that Joe Biden personally nixed Poland’s proposal to reinforce the Ukrainians with MiG-29 fighters. This restraint has the sympathy of some senior Tories, including the former foreign secretary Jeremy Hunt. He tells me: “The truth is we do have to stop ourselves getting sucked into an all-out war between Russia and Nato, because we have no idea how that might end.” Others contend that an excess of caution is handing Putin an advantage that he can and should be denied. Tobias Ellwood, the former soldier who chairs the Commons select committee on defence, argues that it is militarily and morally wrong to “leave the Ukrainians to do all the heavy lifting by themselves” while Nato’s “colossal firepower” is left “sitting on the bench”. The longer the war goes on – and especially if disgusted western voters put more pressure on their governments to respond to Russian war crimes – the more heated this argument will become. Russia is now a pariah state with a siege economy. Sanctions are hurting, but Putin is not being punished as severely as he could be, because western countries are still buying his hydrocarbons. Russia is banking $700m a day from European states for natural gas alone. This keeps the Kremlin solvent, finances its war machine and will be interpreted in Moscow as a sign that the west is not as fully committed to the fight for freedom as it claims to be. The selfish case for not imposing a comprehensive ban on Russian exports is that it will inflict discomfort on western consumers until alternative energy sources are available. The tactical case is that this sanction is a big bazooka best kept in reserve to deter Putin from an escalation of atrocities, such as using chemical or biological weapons. We know from his indiscriminate blitzing of major cities that he is utterly indifferent to the slaughter of civilians. Like Macbeth, he may tell himself “I am in blood stepped in so far that should I wade no more, returning were as tedious as go o’er”. He has already committed so much murder that his next gamble may be that he has nothing to lose from perpetrating even fouler acts. Should that happen, there will be an unanswerable case for tightening the economic blockade of Russia to maximum. Confronted with so much loss and devastation, it is natural to try to find solace in optimistic conjectures about how this war could end. This has been encouraged by battlefield deaths of senior Russian officers, the disappearance of key figures around Putin and reports of mutiny in his army’s ranks. The hope is that casualties and demoralisation on the Russian side will mount to the point that Putin is compelled to call it quits, withdraw his forces and try to dress up humiliation as some kind of victory. The dreamiest “dream scenario” is a putsch in Moscow. Putin contracts what was known in the cold war era as “Kremlin flu”. He goes away and never comes back – unless it is to face a war crimes trial at The Hague. Western governments do discuss the chances of a Kremlin coup. “It’s not impossible,” says Sir David Lidington, the former deputy prime minister and now chairman of the Royal United Services Institute. Russia has often surprised us. Western intelligence agencies didn’t anticipate the toppling of Nikita Krushchev in the wake of the Cuban missile crisis or the coup against Mikhail Gorbachev that triggered the collapse of the Soviet Union. We cannot entirely rule out the dethroning of Putin. But, as Sir David also says, nor should we be counting on it. It will be a major error to overinvest in scenarios that may turn out to be false. Western governments can hope for the best, but they must prepare themselves and their peoples for a protracted and testing conflict. Liberal democracy will not endure unless there is the stamina and the grit to battle for it. Whatever the cost of defending freedom to us, it will be as nothing compared to the sacrifices being asked of the courageous people of Ukraine. Andrew Rawnsley is Chief Political Commentator of the Observer