OPINION: Kostiantynivka, the fortress that holds — but for how much longer?

Introduction: The city Putin wants at any price

36.98% of a city in ruins

On the morning of July 2, 2026, the Institute for the Study of War (ISW) publishes a figure that demands attention: Russian forces maintain a presence across 36.98% of Kostiantynivka's territory. Not a consolidated occupation — an infiltration, a diffuse presence, a progressive grip. And above all, 76.73% of Russia's gains in this city during June 2026 were achieved within that single month alone. The machine is accelerating. The pressure is intensifying. The city holds — but at what cost?

Before the war, Kostiantynivka had nearly 70,000 inhabitants. Today, according to Reuters, approximately 2,000 civilians still cling to their homes in this Donbas city transformed into a permanent combat zone. This is no longer a city — it is a symbol. And symbols, in wartime, carry strategic value that often exceeds their actual military weight.

The southern fortress: what is really at stake in Kostiantynivka

Kostiantynivka is the southernmost city in a cluster of four major urban centers forming what analysts call the "fortress belt" of Ukrainian Donbas. To the north, roughly 15 kilometers away, lie Sloviansk and Kramatorsk — two cities already under constant pressure from airstrikes and drones. Between them, Druzhkivka, about twelve kilometers away, is watching civilian life collapse as fighting draws closer. If Kostiantynivka falls, Russia gains a foothold pointing north — and the road to those three other cities becomes immeasurably more dangerous.

Vladimir Putin has stated that Russia must control the entirety of the Donetsk region before the war can end. Ukraine still controls roughly one-fifth of that region after more than four years of fighting. Kostiantynivka is the lock on the door. That is why Russia has concentrated disproportionate firepower here — and why its defense demands so much.

The timeline of progressive collapse: a chronicle of infiltration

October 2025: the first Russian soldiers enter the city

The ISW notes that Russian forces first infiltrated Kostiantynivka in October 2025. For months, this meant only small groups of soldiers — one or two at a time — slipping into the outskirts, using abandoned buildings as observation posts, probing Ukrainian defenses. No classic front line. A war of building by building, street by street, basement by basement. A war of ghosts that had been running for months before the world truly started paying attention.

It was only in June 2026 that Russia began consolidating those tactical gains. The shift from infiltration to consolidation represents a meaningful qualitative change: this is no longer about testing defenses, but about bypassing them. The battlefield air interdiction campaign (BAI) accompanying these operations aimed to sever Ukrainian logistical lines — to starve them before overwhelming them.

June 2026: the decisive acceleration

In June 2026, Russia concentrated formidable forces around Kostiantynivka: at least one combined arms army and one army corps, with additional elements from at least four other armies and marine infantry formations. This firepower and maneuver capability has no equivalent in what Ukraine can field locally. The imbalance is not tactical — it is structural.

On July 2, 2026, observers counted 20 Russian assaults in 24 hours across the sectors of Novodmytrivka, Illinivka, Stepanivka, and Raiske. Twenty assaults in a single day — this is not positional warfare. It is constant pressure, designed to exhaust, to force errors, to find the crack that becomes a breach. Russia is prepared to pay the human cost to advance.

The geography of resistance: what terrain demands

Kostiantynivka within Ukraine's defensive architecture

The value of Kostiantynivka is only understood through its place within Ukraine's defensive architecture. The city is the southern anchor of the fortress belt. If it falls, Russian forces can project northward along this axis — toward Druzhkivka, toward Sloviansk and Kramatorsk. Those cities are already under pressure: they endure airstrikes and drone strikes on a near-daily basis, their civilian life is on the edge of implosion, their supply lines are fraying.

Occupying Kostiantynivka would give Russia a launching point for a northward push. This would not be a rapid operational breakthrough — the ISW considers this unlikely — but it would open a new phase of pressure on the rest of the fortress belt. And in a war of attrition, each additional phase of pressure increases the risk of progressive collapse.

Logistical routes under permanent fire

One of the most decisive dimensions of the battle for Kostiantynivka is the logistical war. The supply routes from the north are under permanent artillery fire, drones, and guided bombs. Reuters accompanied the "Predator" brigade — a national police unit reconverted into a combat force — patrolling the threatened route against drones and remote-controlled mines. Fiber optic cables running over anti-drone nets stretched above the road are used to guide first-person view (FPV) drones. The sun burns. Mines threaten. And in the "kill zone", it is now ground robots that deliver water, food, and ammunition to frontline soldiers.

A 34-year-old soldier, Oleksandr Kosmin, sums it up in three words: "Everything is done on foot." No vehicles. Too dangerous. Military logistics — the backbone of any defensive effort — is reduced to its most basic expression: the man who walks, carries, and delivers. And hopes no enemy drone spots him.

Voices from the front: the soldiers who hold

The Predator brigade and the drone war

The "Predator" brigade, a unit of the Ukrainian national police, illustrates a reality of this war: Ukraine's defensive forces are no longer composed solely of traditional professional soldiers. Units formed from volunteers and repurposed personnel — like this police brigade — hold entire front sectors. Their immediate mission: secure the vital logistical axis, flush out Russian drone teams operating along the roads, neutralize remote-controlled mines.

This is a very short-range war, extremely dangerous, in which initiative usually belongs to the attacker. Russia can choose the time, place, and method of its assaults. Ukraine must be capable of responding continuously, across the entire perimeter. This tactical asymmetry — an omnidirectional defender facing an attacker who chooses his axis — is one of the fundamental constraints of urban combat in enemy territory.

The civilians who stay: unwilling witnesses

Larysa Sereda, 59 years old, is evacuated in a police vehicle. She says simply: "Why am I leaving? Because I'm afraid. The drones fly." But she adds: "I plan to come back home. I don't want to stay somewhere unknown. The war will end, and I'll come back." This may be the most human sentence in this entire piece. The certainty that one will return. The certainty that the war cannot last forever. The certainty that Kostiantynivka — despite the drones, despite the assaults, despite the ruins — is home.

Nearby, in Druzhkivka, Reuters correspondents witnessed something more brutal: a husband and wife found dead in a van struck by a Russian drone. The white ribbons meant to mark the vehicle as civilian were still fluttering from the roof. Russia makes no distinction between military targets and civilians. It never has. And the world knows it.

Expert analysis: between hope and realism

Emil Kastehelmi: "a matter of time"

Emil Kastehelmi, an analyst with the conflict analysis group Black Bird in Finland, is one of the most rigorous observers of this war. His verdict on Kostiantynivka is unambiguous: the city's fall "appears to be more a matter of time." He specifies that while Ukraine's medium-range strikes on Russian logistics have degraded enemy combat capabilities in rear areas, they have not had sufficient effect to compel Russia to pause its offensive. The Russian machine continues to advance, despite increasingly heavy losses.

This factual assessment is painful. It does not mean the battle is lost today. It means that without significant reinforcement — in personnel, materiel, and logistical resources — the current trajectory points toward an unfavorable outcome for Ukraine. Kastehelmi does not predict imminent collapse. He identifies a trend, a dynamic, a vector. And vectors, in physics as in military strategy, have their own logic.

General Nikoliuk and conditional hope

Against this diagnosis, General Viktor Nikoliuk, commander of Ukraine's Eastern Operational Command, offers a conditional response: Kostiantynivka can hold — provided the current level of personnel and resources is maintained. The nuance matters. He does not say the city will hold. He says it can hold if. That "if" is an implicit acknowledgment of the fragility of the situation.

Ruslan Mykula, from the open-source mapping group DeepState, is even more direct: "A choice will have to be made: either raise the stakes, or withdraw." He adds: "The situation is such that the stakes increase with each passing day." This is not a political position — it is an operational analysis. Ukraine cannot defend Kostiantynivka at minimal cost indefinitely. The question of strategic decision — hold at all costs or reposition — has been put squarely on the table.

Russian firepower: an army that no longer counts its losses

A full combined arms army against a single city

Russia's deployment around Kostiantynivka reveals the strategic priority assigned to this target. At least one combined arms army and one army corps, plus elements from at least four other armies and marine infantry formations — this concentration of force is not incidental. Russia knows this city is the lock. It has decided to break it open, whatever the cost.

And the cost is real. The ISW notes that Russian forces will likely continue to suffer heavy losses to maintain their gains. This is not an army advancing easily — it is an army willing to pay a bloody price to advance slowly. This logic of maximum attrition belongs to a regime that can mobilize men indefinitely, that does not account to its mothers and families in the same way a democracy does.

The structural manpower advantage

Russia's structural manpower advantage is one of the most difficult realities to counter in this war. Moscow can absorb substantial losses and continue sending replacements. Reuters notes that frontline assaults are often reduced to one or two soldiers at a time — suicide sorties designed to identify defenses, draw Ukrainian fire, and locate positions. Behind them, more follow.

Ukraine cannot afford to lose its soldiers at the same rate. Its human resources are limited. The rotation of exhausted units is a structural problem. In the hottest sectors, like Kostiantynivka, the same units have been holding for weeks without relief. Human exhaustion may be the least visible factor in this battle — and one of the most decisive.

Russian strategy: infiltration, BAI, and progressive encirclement

The battlefield air interdiction campaign (BAI)

One of the least-covered aspects of the battle for Kostiantynivka is the battlefield air interdiction campaign (BAI) that Russia is running in parallel with its ground assaults. The objective of this campaign is explicit: deny Ukrainian forces their logistical lines. Without resupply, without ammunition, without rotation, a defensive unit eventually breaks — not because it is overwhelmed, but because it has exhausted itself.

Guided bombs, long-range drones, missile strikes on transport infrastructure — all of this serves that logic. The goal is not to strike the enemy directly, but to cut its arteries. The road heading north from Kostiantynivka is one of the primary targets of this campaign. And its effects are visible: robots in place of vehicles, soldiers on foot in place of logistics convoys, supply lines reduced to their survival minimum.

The pincer encirclement attempts

Russia is also attempting to encircle Kostiantynivka by advancing on its flanks — the pincer movements that are the signature of Russian military doctrine in this war. Reuters notes that Russian efforts to envelope the city through flanking maneuvers progressively raise the cost of its defense for Kyiv. This is not an imminent encirclement — but it is pressure on both flanks that forces Ukraine to extend its defensive line, dilute its resources, and cover more ground with the same personnel.

The sectors of Novodmytrivka, Illinivka, Stepanivka, and Raiske — all hit by the 20 assaults on July 2 — are precisely the zones where flank pressure is greatest. This is no coincidence: Russia seeks to multiply friction points to saturate Ukraine's response capacity.

The 2,000 remaining civilians: a population held hostage

Who stays, and why

Two thousand civilians in a city designed for 70,000. That figure should stop us. These men and women who remain are not combatants. They often cannot leave — for lack of means, out of refusal to abandon a home that an entire lifetime built, or due to physical incapacity. Some stay because they refuse to let Russia make the decision to displace them. This is a form of silent resistance — absurd and courageous in equal measure.

Living conditions in the city are unimaginable. No stable electricity. Little water. Drones sweeping the streets. Shells falling without warning. Abandoned buildings that Russian soldiers use as infiltration positions. And despite all of this, 2,000 people choose, each morning, to stay. This stubbornness is not stupidity — it is dignity.

The collapse of civilian life in nearby areas

In Druzhkivka, roughly ten kilometers away, civilian life is collapsing under the pressure of fighting drawing closer. Residents are being forced out as combat approaches. The couple found dead in their van — with white civilian ribbons still attached — symbolizes the permanent danger facing those who try to move through the region.

Sloviansk and Kramatorsk, roughly 15 kilometers to the north, are enduring air and drone attacks on a near-daily basis. These two cities, still relatively spared a few months ago, are now entering the zone of direct risk. The dynamic is clear: pressure is advancing from south to north, from Kostiantynivka toward the rest of the fortress belt.

The Ukrainian response: holding without the means to hold

Units on the frontline

Kyiv's 19th Army Corps is on the frontline in Kostiantynivka. Its senior commanders have contradicted Putin's version — which claimed Russian control over significant portions of the city — asserting that their troops are "plucking" small Russian groups that manage to infiltrate. This is a more optimistic assessment than that of independent analysts — but it is not incompatible: frontline soldiers defend their sector while analysts see the full picture.

The operational reality is that Ukrainian forces must defend an enormous perimeter — an entire city — with fewer troops than the attacker, under degraded logistical conditions, under unrelenting pressure. Every soldier, every unit, every local commander faces impossible choices: concentrate forces on the most threatened sectors at the risk of leaving others exposed, or hold everywhere at the risk of exhausting everywhere.

The missing reinforcements: the central question

The diagnosis is clear from experts, commanders, and observers alike: without significant reinforcement in personnel and materiel, Kostiantynivka's trajectory is unfavorable. The reinforcement question feeds directly into Ukraine's politically sensitive mobilization policy — and into Western equipment deliveries. Both variables are currently insufficient.

Western allies have promised weapons systems, ammunition, support of every kind. But the pace of delivery does not match the pace of consumption at the front. Russian glide bombs continue to fall. Shaheds continue to strike. And Ukrainian soldiers, with what they have, continue to hold. For how long?

The broader strategic stakes: what the West loses if Kostiantynivka falls

The value of precedent

In every war, cities carry value beyond their geographic or economic weight. Kostiantynivka is not just a city in the Donbas — it is a test. If it falls, Russia will have proven it can take fortress cities in Ukraine's defensive system, even at colossal cost. That precedent would encourage intensified efforts across other sectors of the belt and beyond.

For the West, the fall of Kostiantynivka would also send a signal about the viability of the current support strategy. If weapons deliveries, economic sanctions, and financial support cannot protect key Ukrainian positions, the question of that support's adequacy will need to be raised openly. And in an election year across several major democracies, that question will be weaponized by those seeking an exit.

What Putin really wants

Vladimir Putin does not only need Kostiantynivka militarily. He needs it politically. A visible victory in this sector, over a city that Western media present as a defended fortress, would allow him to demonstrate to his domestic audience that the war effort is bearing fruit. In an authoritarian regime that controls information, symbolic victories carry substantial political value — they justify sacrifices and feed the narrative of inevitable victory.

Denying Putin this symbolic victory is therefore not merely a military matter. It is also a question of psychological warfare and Russian domestic politics. Every week Kostiantynivka holds is a week during which the narrative of an easy victory fails to materialize. And in the information war accompanying this conflict, that counts.

The fortress belt: a defensive doctrine under strain

What the fortress belt is

The concept of the fortress belt refers to the cluster of cities and fortified positions forming the skeleton of Ukraine's defense in the Donbas. These are not classic trench lines — they are urban zones transformed into complex defensive systems, where every building is a potential position, where underground networks serve as protected passageways, where defenders' knowledge of the terrain partially offsets their numerical inferiority.

This defensive model has proven its worth in other Ukrainian battles. Bakhmut, Avdiivka, Pokrovsk — names that evoke months of fierce resistance against constant Russian numerical superiority. But these cities ultimately fell, often after months of fighting. The question is not whether the model works — it does — but how long it can hold against sustained pressure and insufficient Western deliveries.

After Kostiantynivka: the scenario no one wants to contemplate

If Kostiantynivka were to fall, the next line would be Druzhkivka, then Sloviansk and Kramatorsk. These cities matter not only militarily but symbolically: they are urban centers with infrastructure, significant populations, and deep identity value for Ukraine. Their loss would be a major political shock for Kyiv — and a propaganda windfall for Moscow.

The ISW specifies that even if Russia advanced from Kostiantynivka, a rapid operational breakthrough against the fortress belt as a whole remains unlikely. The belt is not a single line that collapses all at once — it is a system of defense in depth. But every lost node weakens the entire system. And the progressive weakening of a defensive system is the prelude to its eventual collapse.

The world watches: allies and their responsibility

What arms deliveries mean in concrete terms

The battle for Kostiantynivka is, among other things, a measure of Western allies' willingness to support Ukraine concretely. Not in declarations, not in promises at summits — but in weapons systems delivered on time, in sufficient quantities, with the training and ammunition required. The list is long: air defense systems to counter drones and glide bombs, armored vehicles for logistics under fire, artillery ammunition to maintain fire parity with Russia.

Every item on that list has been promised. Every item has been partially delivered. Delays, political hesitations, industrial constraints of allied nations — all of it adds up to a gap between what Ukraine receives and what it needs to receive. That gap, invisible in official communiqués, is very visible on the ground in Kostiantynivka.

The role of Western public opinion

The durability of Western support for Ukraine depends in part on public opinion in the countries involved. And public opinion is sensitive to narrative: if Ukraine is perceived as losing ground despite billions in support, skepticism grows. If it is perceived as heroically resisting an unjust aggression, support holds.

The battle for Kostiantynivka is therefore also an information battle. The 20 assaults in 24 hours, the 2,000 remaining civilians, the 36.98% of city partially infiltrated — these figures tell a story. The story of a city holding against crushing pressure. The story of a war that continues to demand support the West cannot and must not withdraw.

What I take from July 2, 2026: a personal reckoning

The facts I cannot ignore

I return to the facts. On July 2, 2026, Russia controls approximately 37% of Kostiantynivka's territory, achieved three-quarters of its gains in that city during June alone, and has concentrated formidable military power there. Twenty assaults occurred in a single day across peripheral sectors. The most serious analysts say collapse is a matter of time without reinforcements. And Ukraine has not yet received those reinforcements.

I also note this: the ISW judges a rapid operational breakthrough unlikely. Ukrainian resistance is real and documented. The Ukrainian army defends this city with a tenacity that commands respect. And the global front dynamic — stagnant elsewhere — suggests that Russia is paying a very high price for every meter gained. These nuances matter. The situation is serious, but not desperate. Grave, but not irreversible.

What I believe about what comes next

I believe Kostiantynivka can hold. I believe Ukrainian resistance has demonstrated, again and again in this war, a capacity to defy pessimistic forecasts. I believe that every additional week of resistance raises the cost to Russia and weakens its ability to sustain offensives at the same intensity. But I also believe this resistance has real physical and human limits — and surpassing those limits without increased external support is a matter of luck, not strategy.

My conviction, in closing: the international community must treat Kostiantynivka for what it is — a test of the West's collective will. A test whose result has not yet been written. A test being run right now, with men and women in the ruins, robots carrying rations through a kill zone, and white ribbons on civilian vans. The answer also belongs to our political leaders.

Conclusion: the fortress holds — the choice belongs to the West

The question that will not have an immediate answer

Will Kostiantynivka hold? The honest answer, on July 2, 2026, is: perhaps. With the right reinforcements, at the right time — yes. Without them, under the current dynamic — no, probably not. That "perhaps" is not intellectual surrender. It is the accurate translation of an open military situation, in which several variables remain undetermined: the pace of Western deliveries, Ukraine's capacity to mobilize reinforcements, the durability of the Russian effort despite its losses.

What we know with certainty is that the battle continues. That Ukrainian soldiers are holding. That the 2,000 remaining civilians are hoping. That analysts are watching with concern. And that political leaders in Washington, Berlin, Paris, Ottawa, and elsewhere hold in their hands part of the answer to whether the fortress will hold.

The frontline moves in real time

While I write this opinion piece, the front line is shifting. Not dramatically, not by the hour — but by the day. In Druzhkivka, residents are fleeing. In Sloviansk, strikes are daily. In Kramatorsk, normal life contracts under the pressure of air raid alerts. This slow movement, measured in meters per day on maps, is measured in human lives on the ground.

Russia does not need a spectacular breakthrough to win this battle. It needs time. To maintain pressure. To ensure that the cost of resistance exceeds Ukraine's capacity to absorb it. This is the strategy of strangulation. And it is advancing. Slowly. Inexorably. Unless something changes.

What "something changes" means concretely

Changing something means: delivering the promised weapons systems without further delay. Authorizing Ukraine to use those systems without geographic restrictions that prevent striking Russian logistical bases nearby. Maintaining the economic sanctions that deny Russia the technologies it needs to fuel its war machine. And supporting politically, with consistency and without ambiguity, Ukraine's right to defend its territory — including Kostiantynivka, including the cities of the fortress belt, including all the land Putin claims to have annexed.

This is a demanding agenda. It is not an impossible one. And faced with the alternative — a Donbas entirely under Russian control, a catastrophic precedent for European collective security, and a Russia confirmed in its conviction that military aggression pays — it is the only morally and strategically defensible option.

Conclusion: hold the line, hold the course

What this opinion piece says and does not say

This piece does not predict the fall of Kostiantynivka. Nor does it predict indefinite resistance. It describes a documented, serious, urgent military reality — and it asserts that this reality demands a political response from the West equal to what is at stake. The 36.98% of city infiltrated, the 20 daily assaults, the 2,000 civilians remaining, the 76.73% of Russian gains in a single month — these are facts. They do not disappear by being ignored.

This piece also asserts this: Ukrainian resistance deserves better than calculated discussions about what the West can "afford" to deliver. It deserves a response equal to the challenge. And that response — massive deliveries, sustained support, firm rejection of sanctions fatigue — is both possible and necessary. The rest is a matter of political will. And political will is also built by pieces like this one.

Kostiantynivka, July 2026

On the morning of July 2, 2026, Ukrainian soldiers are holding Kostiantynivka. Robots are delivering rations in the kill zone. Civilians refuse to leave. Analysts are studying the maps with concern. And Russia continues to attack — twenty times a day, with everything it has. That is the reality of July 2, 2026. That is what I wanted to write. No more. No less.

The fortress holds. For today, the fortress holds.

By Maxime Marquette, columnist

Columnist's transparency note

Stated biases

I am in favor of Ukraine and its defense against Russian aggression. This opinion piece is written from that clear, stated position. I do not claim neutrality in a conflict between an aggressor and a nation defending its territory. I note, however, that all numerical data cited in this piece come from verifiable primary sources: the ISW, Reuters, the DeepState group, and official Ukrainian statements. I invented no figure, no quote, no fact.

My risk assessment for Kostiantynivka reflects the consensus of the serious analysts I cited. It does not reflect personal certainty about the military outcome — which remains open — but an honest reading of documented trends as of July 2, 2026.

What I do not know

I do not have direct access to Ukrainian military plans nor to the precise intentions of the Russian command. My analysis is based on high-quality open sources — not classified intelligence. There are elements I cannot assess from my position as a columnist: the precision of ISW figures on territorial occupation, Ukraine's real reserve capacity in this zone, and the exact durability of the Russian effort given its losses. These limits are real and I acknowledge them.

Sources

Primary sources

ISW — Russian Offensive Campaign Assessment, July 1, 2026 — July 1, 2026

Reuters — Russia pounds on the gates of Ukraine's 'fortress belt' — June 29, 2026

Ukrainska Pravda — Situation update Kostiantynivka — July 2, 2026

Secondary sources

TSN — Russian forces advance along two axes — July 2026

Censor.net — Russian Federation attacks defence forces 73 times — July 2026

Daily Kos — Ukraine war situation July 1, 2026 — July 1, 2026