The war in Ukraine is changing — and the West now faces a stark choice

The inevitable fall of Mariupol — Ukraine's long-suffering eastern port on the Sea of Azov, now besieged, pounded to dust and soaked in the blood of its residents — will carry with it a heavy symbolism, the kind observers say western allies need to reflect upon urgently.

Already, it has the potential to change the trajectory of war. Ukrainian President Volodomyr Zelensky warned this week that peace talks will end if Moscow "eliminates" the city's defenders.

More than that, the end of the merciless blockade of Mariupol will free up Russian combat forces to concentrate on a growing offensive in the eastern Donbas region, which the regime of Russian President Vladimir Putin claims it wants to "liberate" from Kyiv's control.

And that will mark a turning point in the war, one that will force western allies to make a choice, said a former senior U.S. Army and NATO commander.

"I think the bigger problem for us, or the bigger challenge — that's the collective 'us', this includes Canada — is we have to decide that we're going to win," retired U.S. lieutenant-general Ben Hodges told CBC News.

"It's not about just keeping Ukraine in the fight. It's about winning. And that means we're going to do everything necessary to make sure that Ukraine is successful that does not require putting American or Canadian or British troops on the ground."

Ukraine's efforts to defend itself have been nothing short of extraordinary. Russia is concentrating on the Donbas now after Ukrainian forces pushed Russian troops back from Kyiv. Ukrainian soldiers continued to hold their positions in Mariupol Tuesday night.

But efforts to articulate the West's longer-term war aims — beyond the near-term goal of helping Ukraine survive — have been hit-and-miss. U.S. President Joe Biden offered an unexpected moment of clarity when, during a speech in Poland, he said Putin could not remain in power — a statement immediately clarified by the White House to downplay the suggestion of regime change.

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In her recent budget speech, Canada's Deputy Prime Minister and Finance Minister Chrystia Freeland said western democracies will not be safe until "the Russian tyrant and his armies are entirely vanquished" — and the West is counting on Ukraine to do that.

Such talk brings with it the risk of a wider war, but Hodges said allies now need to be clear about where their support of Ukraine is going and what — if anything — would be gained by negotiating with Russia.

"They smash cities. They murder innocent people. It's a medieval application of power, and I think that if there's ever going to be any sort of negotiated outcome, we need to have our eyes wide open about who it is we're dealing with," he said.

Hodges said that, regardless of Mariupol's fate, Zelensky would have found it tough to sit across the table from Putin given the string of reported atrocities his government has laid at the feet of retreating Russian troops.

Dominique Arel, chair of Ukrainian studies at the University of Ottawa, said he doesn't think "there's anything to negotiate right now" because Russia has made it "very, very clear that it wants to conquer all of Donbas and even a bit outside now."