Opinion editor's note: Editorials represent the opinions of the Star Tribune Editorial Board, which operates independently from the newsroom.

•••

After Ukraine's initial, inspiring victories over Russian invaders in Kyiv and other critical western and central cities, its intrepid military faces fierce fighting and significant setbacks in eastern Ukraine.

The more open terrain works to Russia's military advantage in weaponry, including more long-range artillery. The gains have advanced and consolidated Russian President Vladimir Putin's revised goals of seizing the eastern Donbas region.

While the West has responded to Russia's February full-scale invasion of Ukraine with unexpected diplomatic, economic and military unity, divisions are becoming more apparent between Western and Eastern European nations.

Warsaw and other eastern capitals believe Moscow's aggression won't stop at the Ukrainian border and that the Kremlin must be defeated for long-term security in Europe. While Western European nations certainly want Ukraine to prevail, they appear more focused on a negotiated settlement than the ongoing military campaign, which could turn into a longer slog or even a so-called "frozen conflict."

Three Western leaders — French President Emmanuel Macron, German Chancellor Olaf Scholz and Italian Prime Minister Mario Draghi — will soon meet with Ukrainian President Volodymyr Zelenskyy in Kyiv in a show of support. But what matters most beyond the event is what they say and do to shore up Ukraine's flagging military prospects. Macron, in particular, has not been rhetorically helpful by twice saying it is important not to "humiliate" Putin, as if Russia's ruler's emotions are more important than the deaths of Ukrainian citizens — and perhaps of their country.

Increasingly public pleas — and complaints — from members of Zelenskyy's government on the amount and pace of allied arms delivery threaten to widen the divide. That would play right into Putin's apparent belief that Western resolve will weaken.

Italy, Germany and France in particular "have by and large been rather weak in recognizing the danger of Putin's foreign policy, and weak in helping Ukraine respond to the aggression of the past eight years," former U.S. Ambassador to Ukraine John Herbst told an editorial writer in reference to Russia's annexation of Crimea and destabilization of eastern Ukraine. Herbst, now the senior director of the Atlantic Council's Eurasia Center, added that conversely, like Ukraine, "Poland sees things clearly because their very security and even perhaps existence as an independent nation depends upon seeing things clearly."

Diplomacy can and should ultimately play a significant role in stopping Putin's war of choice. But the only way Putin will negotiate, and the only way Ukraine can succeed, is if the country is on a better strategic footing. And that won't happen if the West isn't as aggressive in delivering arms as the Ukrainians are in using them.

"Putin's aggression goes beyond Ukraine," Herbst said. "There will be negotiations when Putin realizes he cannot achieve his objectives by aggression. Right now, he still thinks he can." Calling for negotiations too soon, Herbst added, is interpreted by Putin "as the absence of Western resolve to provide Ukraine with the support that we should be providing."

Herbst said Ukraine's requests could be met within the recently allocated tranche of about $40 billion in U.S. military and civilian aid, a laudable commitment by Congress, President Joe Biden and the American people. But which weapons — and how many — are sent is the most pressing matter now. When U.S. Secretary of Defense Lloyd Austin meets his European counterparts in the coming days, he should prod the alliance to level the battlefield, so Ukraine is strengthened at the negotiating table.