Here is what Ukraine probably wants from its wild assault on Russian territory

• Ukraine's attack on Russia's Kursk region was a shock move in a mostly static war.
• Experts are analyzing why Ukraine made the move, which caught Russia off guard but may be hard to sustain.

Ukraine has surprised the world with its attack on Kursk, a rare ground invasion of Russian soil.

Most onlookers "didn't think they had the forces up their sleeves spare to do this," Patrick Bury, a military analyst at the UK's University of Bath, told Business Insider.

As of Monday, the Kremlin announced that Ukrainian troops had advanced almost 19 miles into the western Russian region.

In a public meeting that afternoon, Russian President Vladimir Putin instructed his military to purge Ukrainian troops from Kursk. The attack would not go unanswered, he said.

The extent of the advance is still unclear — as is Ukraine's calculus in making the high-risk attack.

One anonymous top official, speaking to Agence France-Presse, gave three rationales.

"The aim is to stretch the positions of the enemy, to inflict maximum losses and to destabilize the situation in Russia as they are unable to protect their own border," he said.

But there may be more at play.

Experts who spoke to BI stressed that their assessments of Ukraine's actions were still speculative given the lack of firm information.

"We're not sitting inside a bunker in Kyiv," as Matthew Ford, a war expert and lecturer in international relations at the UK's University of Sussex, put it.

But with those limitations, they proposed several goals that Ukraine may well have in mind while attacking Kursk.

Straining Russia's ability to hold other territory

Echoing the Ukrainian official, experts suggested Ukraine was seeking to stretch Russia's resources along its main front lines within Ukraine.

"If the Russians are moving reserves from the South, then the Ukrainians may well be relieving pressure across their frontline," Ford said.

Matthew Savill, director of military sciences at the London-based Royal United Services Institute, assessed on Monday that some Russian troops had been moved from within Ukraine, but the scale is unclear.

But, Ford pointed out, Ukraine could well be thinning out its own lines to do this.

Savill also suggested that the attack may be connected to other undeclared efforts, either as a diversion or as a supporting fight.

For example, it could be intended to weaken the supply lines supporting the remains of the Russian forces left over from Russia's fumbled attack on Kharkiv earlier this year, he wrote in an assessment seen by BI.

A message to the West

Ford pointed to Western onlookers — some of whose governments are wavering on supporting Ukraine — as a possible audience for the attack.

"A lot of analysts were talking at the beginning of the year about how Russia would have a lot of advantages," he told BI.

Ukraine started 2024 in a deep bind: its largest military supporter, the US, stalled for months on sending more aid. Ukraine's own parliament dithered over conscription, leaving few new troops for the front.

That picture was top of mind for many international commentators for months.

"So this operation looks like a good two fingers up against any of the Western analysts who were saying, 'well, Russia's going to come out on top,'" Ford said.

He said this would likely only be incidental to Ukraine's main strategic goal in the Kursk attack.

Kyiv may intend to send "a signal to international backers that Ukraine is still in the fight, especially ahead of US elections," according to Savill.

But Bury believes this may indeed be central to Ukraine's thinking.

An attack like this would need lengthy planning, he said — suggesting it was first conceived back in a time when the Pentagon was urging caution, and a second Trump presidency looked the likeliest it's ever been.

"So therefore you can see the Ukrainians thinking this is high stakes," he said, saying they were possibly thinking: "'Now we've got to do something if we're going to be potentially forced to the table.'"

A morale boost for a weary force

Ukrainian forces have, for much of the year, withstood relentless assault along a 600-mile front line with almost no opportunity to move forward.

Savill said the attack could be "about boosting Ukrainian morale after months on the defensive."

The country's most notable blows this year — hits on Russian oil facilities, or naval drone strikes in the Black Sea — have all been hundreds of miles away from those fighting on the ground.

With the main defense so heavily dependent on Western support, grabbing the initiative on Ukraine's own terms like this is only going to help morale, Ford said.

"You need some way of making everyone actually feel like they've got some control over their own future rather than just reliant on whatever the West wants to do," he said.

Ford added, though, that it "could easily turn if they take losses which are hard to replace."

Producing bargaining chips

Experts also remarked that Ukraine has opened up — even if only temporarily — the opportunity to grab leverage in both human and territorial form.

It could be an opportunity to capture prisoners of war for prisoner exchanges, Savill wrote.

On August 8, Ukraine released video that it said showed dozens of Russian soldiers surrendering in Kursk, in footage that BI couldn't independently verify.

If Ukraine dug in and managed to hold onto some of the region, the land itself could also become a bargaining chip in negotiations down the line.

"It's high risk, high reward — take some Russian territory and then use that as leverage to try and get some of its territory back if it was forced into negotiations," said Bury.

"I think that is the most likely strategic aim."

Putin, in his Monday remarks, also suggested that Ukraine's actions were to strengthen its hand in a future negotiation.

Ford, though, had some doubts that Putin would anyway respond amenably to possible territory exchanges.

"Putin has a long history of being quite willing to destroy things rather than allow his adversary to have it," he said.

"His track record is not one where he makes deals easily," he added.

Infuriating Putin — and testing his limits

This fight could also be a nerve-racking test of Putin's own red lines.

"It is already clear that Ukraine's decision to invade Russia has succeeded in making a complete mockery of Vladimir Putin's red lines and the West's fears of escalation," UkraineAlert editor Peter Dickinson wrote in an Atlantic Council piece published Sunday.

Putin has said that he would use nuclear weapons if there were a threat to the existence of the Russian state.

"The further the Ukrainians push into Russia, and the less resistance that they get from Russian armed forces, the more I worry that Putin would want to use a nuclear bomb," said Ford.

It's clear that at the very least, the attack is a humiliation for Putin and a radical reminder of the war's reality in Kursk — even if Putin's own power is unlikely to be much undermined.

Anonymous officials talking have said that Putin has taken it "like a slap in the face."