After weeks of diplomatic tangos and hesitation, decisions are afoot that will see more modern Western combat tanks dispatched to Ukraine as the country gears up for anticipated Russian offensives with spring approaching. 

On Wednesday the German chancellor, Olaf Scholz, was set to announce that Berlin will approve supplying state-of-the-art Leopard 2 battle tanks to Ukraine. While Mr. Scholz has long been conflicted about this move for various reasons, the reversal signifies a breakthrough that could tip the balance of the war in Ukraine’s favor. Predictably, it already has the Kremlin grumbling. 

Germany’s position with respect to arming Ukraine as it struggles to shake off Russian forces has long been seen as less than unequivocal. The turnaround was effected in close coordination with Washington, which is concurrently set to formalize the delivery of about 30 Abrams M1 tanks to Ukraine. The Wall Street Journal reported that President Biden made the decision to do so in a January 17 phone call with Mr. Scholz. 

The German leader clearly needed some coaxing. Earlier this month at Davos, Mr. Scholz said that “we never do anything alone” and that “we must prevent this becoming a war between Russia and NATO.” Russian memories of Germany’s military history in the previous century linger well into this one. Reading between the lines, it is not difficult to surmise that the German chancellor did not want to be perceived as the first or only NATO member to challenge Moscow with game-changing attack weapons.

News about the Abrams tanks was also something of a reversal: just last week, the AP reported that the undersecretary of defense for policy, Colin Kahl, told reporters that the Abrams is a complicated, expensive, difficult to maintain, and hard to train on piece of equipment. Mr. Kahl said that one thing Secretary Austin has been very focused on “is that we should not be providing the Ukrainians systems they can’t repair, they can’t sustain, and that they, over the long term, can’t afford, because it’s not helpful.”

The Abrams tanks are less suitable for the Ukrainian terrain and are said to be too large and complex to be used effectively by Ukrainian soldiers quickly, while the Leopards are nimbler and equipped with integrated weapons systems that will do a better job of putting the Russians on the back foot. Washington’s decision to deliver some Abrams to Kyiv, which will be done through a specific program of assistance to Ukraine and without drawing on U.S. Army stocks, should not be seen as purely symbolic, but there is little doubt that it nudged Berlin toward changing its tune. 

Germany is now likely to not only deliver a limited number of Leopard 2 A6 tanks to Ukraine but also to authorize other countries that already have them, notably Poland, to do the same. According to the weekly Der Spiegel, Berlin will start by sending at least 14 Leopard 2 tanks taken from the stocks of the German armed forces, or Bundeswehr, which has about 320 in total, but of which only 200 to 250 are said to be operational. The AP reported that the goal is for Germany and its allies to provide Ukraine with a total of two battalions, or 88 tanks.

Not everyone in Germany is happy about the decision. The chairman of the Bundeswehr Association, André Wüstner, told a Germany morning television program that the tank delivery is “good for the Ukraine on the one hand, bad for the operational readiness of the Bundeswehr on the other hand.” Separately, Der Spiegel reported that “the Bundeswehr’s operational readiness will be further weakened by the expected delivery of Leopard main battle tanks from Germany to Ukraine.”

Be that as it may, the fight of this century is raging  well east of the Rhine. On Tuesday, President Zelensky said in unambiguous terms that Russia is readying a new offensive. “The occupiers are already increasing pressure in the Bakhmut, Vuhledar, and other directions,” Mr. Zelensky stated. “And they want to increase pressure on a larger scale.” 

That also means more Russian boots on the ground: “In order not to recognize the mistake of aggression,” the Ukrainian leader also said, “the masters of Russia want to throw more of their people and equipment into the fighting.”

The Kremlin spokesman, Dmitry Peskov, bristled that German and American decisions on the tanks amounted to “a rather disastrous plan.” Mr. Peskov cited “technological aspects” as part of the “absurdity” of the development, adding with customary Kremlin ire that “these tanks will burn down just like all the other ones … except they cost a lot, and this will fall on the shoulders of European taxpayers.”

Russia’s ambassador to Washington, Anatoly Antonov, said on Wednesday, “It is obvious that Washington is purposefully trying to inflict a strategic defeat on us,” adding that if the U.S. “decides to supply tanks, then justifying such a step with arguments about ‘defensive weapons’ will definitely not work. This would be another blatant provocation against the Russian Federation.”

The view from Kyiv is more pragmatic: Eject the Russians sooner rather than later or risk watching Western support diminish over time and the bleak prospect that a war one month short of its first anniversary could devolve into a years-long, low-intensity conflict. 

Hundreds of Leopard tanks, along with Abrams and a number of British Challenger 2 tanks, could help Ukraine win, as Mr. Zelensky knows. With more and better tanks, Ukraine can increase the odds of breaking through Russian lines in the Donbas in the spring, with the goal of splitting the Russian contingents into northern and southern sections. If Ukraine can manage that, it will have a much better chance of turning Himars rocket launchers against the Kerch Bridge that joins the Russian mainland to Russian-occupied Crimea. 

More than any diplomatic tussling, the destruction of that key supply link would make Vladimir Putin sit up straight at one of his long tables. That is something Mr. Zelensky — who has said that Russia’s war on Ukraine started and will end in Crimea — knows too.