BERLIN — Ukraine’s northern toehold at Kursk is tenable for now, but the incursion into Russia draws critical manpower and materiel from Donbas, exacerbating mounting pressure on that eastern front, a retired major general in the Australian Army, Mick Ryan, tells the Sun.

Speaking at the sidelines of an event hosted by the Democratic Strategy Initiative, a security think tank at Berlin, General Ryan called the Ukrainian foray into Russia “important.”

“It’s… a statement of what the Ukrainians are capable of,” General Ryan said. “But whether the retention of Kursk has an impact on the Russian calculus in due course, we’re not quite seeing that yet.”

General Ryan is now an adjunct fellow at the Center for Strategic and International Studies, a foreign policy and national security think tank, following his 35-year career in the army.

Kyiv’s blitz into Russia — the first time since World War II that a foreign adversary has occupied part of that country — may prove tricky to defend in the long term, General Ryan says.

“I think if Ukraine chooses the right terrain, they can defend it for a while,” General Ryan says, adding that the foray into Russia “will absorb a lot of Ukrainian resources, not just ground forces, because the Russians will be throwing everything at them.”

For now, Russia’s response to Kyiv’s incursion into their territory has been slow to materialize, a nod to Kursk’s distance from the halls of power at the Kremlin and importance — or lack thereof.

President Zelensky has touted the number of prisoners Ukrainian troops managed to sweep up during their invasion, useful for future prisoner exchanges. Simply taking prisoners isn’t enough, though, according to General Ryan.

The Ukrainians “clearly want to get as many of their prisoners back through prisoner swap. And I think that’s logical, but that can’t be the strategic rationale for this operation.”

“Just given the cost and the opportunity costs of the operation,” General Ryan says, “there has to be a higher political outcome from the battlefield success.”

General Ryan calls Ukraine’s military-material like air defenses and electronic warfare equipment “scarce,” but the Ukrainian salient into Russia benefits from relatively short supply lines a mere 25 miles from the border.

“There will be a liability for some of these resources to ensure the Ukrainians can conduct a survivable and sustainable defense,” of the Kursk area, General Ryan explains.

He added that the push into Russia competes for resources and will “potentially have an impact on other operations in the east and in the south of Ukraine.”

Ukrainian defenses in the east, at Pokrovsk, are buckling amidst an incredibly costly but sustained Russian assault exacerbated by deep-set exhaustion, mismanaged defense preparation, inexperienced soldiers, and staff-level organizational issues.

Amidst uncertainty on the ground in the east, Mr. Zelensky reshuffled his cabinet, reassigning his foreign and strategic industries ministers along with several other members of his staff.

Mr. Zelensky has shaken up his cabinet and advisor groups before. In February, he appointed General Oleksandr Syrskyi, the architect of the Kursk offensive, as Commander-in-Chief, replacing the widely-respected General Valerii Zaluzhnyi.

That leadership adjustment, along with a recent raft of newly supplied military technology, including aircraft, raised hopes for Ukraine in the spring ahead of the summer months when the ground is dry and ideal campaign season.

And though Ukraine now operates a small fleet of Western-supplied F-16 fighter jets, they have yet to exert significant pressure on Russian forces in Ukraine.

Kyiv has already lost several F-16 pilots and an aircraft, prompting the dismissal of the commander of the Air Force, Lieutenant General Mykola Oleschuk, in late August.

The Ukrainian pilot and maintainer training pipeline is abbreviated, a concession to wartime expediency, and air superiority will remain elusive in the short and medium term.

Still, the director of the Democratic Strategy Initiative, a Berlin think tank, Ben Tallis, tells the Sun that Ukraine’s push into Russia proper represents more than just a victory on the battlefield.

“The Kursk offensive had a positive effect on morale, dented Putin’s image as a competent defender of Russia, and could have gained Ukraine a potentially useful bargaining chip,” Mr. Tallis says.

“Now Ukraine needs to show how this fits into the bigger strategic picture to secure its political as well as military gains.”

On the battlefield, Ukrainian soldiers gird for a brutal winter, while on the home front, Ukrainian civilians contend with severely degraded energy infrastructure. The question now is if the roads to Kursk will lead, eventually, to victory.