Alexei Navalny, persecuted, tortured and murdered by Vladimir Putin, was – to borrow the title of the Russian poet Mikhail Lermontov’s most celebrated work – “a hero of our time”. His courageous fight against the venality and brutality of Russia’s regime, and his championing of democratic choice and human rights, placed him at the forefront of today’s global struggle between liberalism and authoritarianism.

Yet unlike Pechorin, the central character in Lermontov’s 1840 novel of rebellion and disillusion, Navalny did not see himself as a hero or in any way exceptional. He was essentially a man of the people. He spoke for the common man and woman – and he spoke with a smile. And that, more than anything, was what Russia’s humourless, uncharismatic killer-president could neither accept nor forgive.

Navalny’s death last week in prison, which has now been confirmed, provoked shock, anger and revulsion around the world. Although his supporters and admirers, inside Russia and abroad, had largely accepted that he would not be freed as long as Putin ruled, hope persisted that his life, unlike those of so many of the tyrant’s critics, would be spared.

The fact that this hope has been cruelly and suddenly extinguished is chilling. For Russians opposed to the regime – and there are many more than the Kremlin cares to admit – Navalny’s death must seem a disaster. In Moscow, St Petersburg and other cities, people braved the harassment of heavy police deployments to place flowers and hold vigils at monuments to victims of repression. Protests also took place across Europe.

Yet the intimidating message sent by Putin and his cronies to Russia’s citizens is unmistakable: “The regime is all-powerful. Dissent is futile. Defiance is dangerous. Foreign governments, for all their ‘hysterical’ outrage, sanctions and threats, cannot help you. Keep your heads down and don’t dare challenge us. Remember what happened to Navalny.”

Why did Putin choose this exact moment to act? After all, Navalny had been at his mercy since his arrest in 2021, when he returned to Russia after miraculously surviving an attempt to assassinate him with a novichok nerve agent. Putin’s move may be related to next month’s stage-managed presidential “election”. His banning of all credible opponents means he is assured of victory. But he is taking no chances. He wants a big turnout and a big win.

It’s possible, too, that Putin believes he is on a roll in his confrontation with the west, principally over the war in Ukraine. Kyiv’s forces are pinned down along the eastern frontlines and face a more plentifully armed and equipped foe. Ukrainian troops were forced last week to withdraw from the city of Avdiivka to avoid encirclement – a retreat that represents the biggest Russian success since the fall of Bakhmut nearly a year ago.

The failure of European countries to meet their own targets for ammunition and artillery shell production is steadily undermining the resistance of Kyiv’s troops. Putin, doubtless encouraged by this, will also be closely monitoring American political weakness. President Joe Biden has so far failed to deliver a new military aid package for Ukraine, blocked by Republicans in Congress. He is also increasingly distracted by November’s election. Donald Trump’s irresponsible attacks on Nato are a great boon to Russia.

All these factors may have combined to persuade Putin that this was an opportune moment to rid himself of Navalny. He seems to think he can do whatever he likes with impunity. Is he wrong? Is he winning? These are the pressing questions that the western democracies, many of whose leaders attended this weekend’s Munich security conference, must now ask themselves.

Their condemnations of Navalny’s killing were swift and fierce. Biden called Putin a killer, Canada’s Justin Trudeau said he was a monster. But words, however harsh, are no substitute for a plan to reverse what is beginning to look like a losing trend on Ukraine’s battlefields, and to push back the broader, authoritarian tide that Putin symbolises. As we have argued previously, Nato should be doing more to halt Russian aggression. If it had acted earlier, less cautiously, Ukraine would be in a better place.

Biden must now provide Kyiv with the longer-range missiles, capable of hitting targets deep inside Russia, that he has so far withheld. Likewise, more and better combat aircraft to deny Ukrainian airspace to Russian forces are required. Nato ships should help secure Black Sea ports and grain export routes. And delivering the stalled US aid package is crucial. Does Biden really want to be remembered as the president who “lost” Ukraine?

As for Putin and his evil regime, the threatened consequences arising from Navalny’s murder should include urgent action to confiscate billions in Russian state funds and assets frozen since the full-scale Ukraine invasion began two years ago this week. This money, plus the interest accrued, should be used for reconstruction. The allies should also clamp down harder on businesses and countries, such as Hungary, Turkey, India and China, that circumvent sanctions – and break off diplomatic relations with Moscow. Expel its lying, scheming diplomats. Send them all packing.

It’s time to get real with Russia. Like it or not, the west is in an existential battle it must win. After Navalny, it’s time to drop any lingering illusion that Putin’s Russia is a normal country, that it may be reasoned with. Russia has gone rogue. It is a killer regime. It is a menace to its own people and the entire democratic world.