Ukraine’s War of Endurance: Entering a Fifth Year
The full-scale Russian invasion of Ukraine will mark a grim milestone on February 24th, entering its fifth year. For Ukraine, the conflict began with Russia’s 2014 invasion. For Russia, the “special military operation” has surpassed the length of the Soviet Union’s “Great Patriotic War” (1941-1945) and has resulted in hundreds of thousands of casualties.
The 2022 invasion, initially intended as a swift subjugation of Ukraine, has evolved into Europe’s largest conventional conflict since World War II. What began as a war of maneuver, characterized by speed and surprise, has transformed into one of prepared defenses, incremental advances and protracted sieges. Since 2023, the conflict has become increasingly positional, attritional, and focused on adaptation and endurance.
Ukraine’s strategy centers on making the war unsustainable for Russia by minimizing territorial losses, increasing Russian casualties beyond Moscow’s recruitment capacity, and escalating economic costs. Ukraine is leveraging its growing long-range strike capabilities, targeting Russia’s energy export infrastructure in an attempt to create a financial breaking point for Moscow and compel substantial revisions to its negotiating demands in 2026. Russia, conversely, aims to achieve breakthroughs through sustained offensive pressure or to cripple the Ukrainian economy and displace its population through bombardment of critical infrastructure. However, Russian offensives have consistently fallen short of their objectives, and Western support for Ukraine has remained resilient.
Despite a difficult position entering 2026 – with cities rationing electricity and the military facing manpower shortages – Ukraine performed well in 2025, arguably ending the year in a stronger position than in 2024, when Russian forces were advancing more rapidly. While Russia briefly slowed its offensive pace over the winter, it was picking up again by late January. Kyiv spent much of 2025 strengthening its relationship with Washington and establishing mechanisms to ensure continued Western support. Ukraine’s drone advantage has diminished, but its overall position is not desperate. Russia cannot achieve its political goals through military means alone, as capturing even small territories requires considerable time and comes at a steep cost.
The Early Years of the Conflict
Initial perceptions of the war proved inaccurate. In February 2022, Ukraine appeared on the brink of collapse, with U.S. Intelligence indicating Russia was preparing to seize most of the country and install a pro-Russian regime in Kyiv. However, Ukraine’s government remained skeptical of a full-scale invasion until the last moment, and key U.S. Allies held differing interpretations of the intelligence. Washington anticipated a successful initial Russian phase followed by a difficult occupation, believing Russian forces could quickly isolate Ukrainian forces and shock the leadership with strikes. These assumptions proved false.
The Russian military encountered fierce resistance and was unprepared for a major conventional war, while Ukraine rallied international support. Following defeats in Kyiv and southern Ukraine, Russian forces redeployed and leveraged their firepower advantage. As Ukraine’s ranks swelled with volunteers and received Western intelligence and capabilities, the Russian offensive was exhausted by the summer of 2022. Ukraine launched successful counteroffensives in Kherson and Kharkiv, leading to a major Russian rout. These gains, however, created expectations for a swift Ukrainian victory.
Moscow responded with a partial mobilization, sending hundreds of thousands of troops to the front and investing in expanding defense industrial production, signaling a commitment to a long war. The costly battle for Bakhmut, from August 2022 to May 2023, foreshadowed the difficult fighting ahead. Ukraine’s focus on Bakhmut and the resulting casualties overshadowed plans for a decisive summer offensive in 2023. Western hopes for a breakthrough were unmet, and preparations for a prolonged conventional war were lacking. Russian forces were dug in with reserves, and the attack lacked surprise.
The Ukrainian summer offensive failed, leading to recriminations between Washington and Kyiv. Russia attempted to regain the initiative, but, like Ukraine, could not overcome prepared defenses backed by precision strikes and drones. The battlefield had changed, with drones largely preventing the concentration of forces or maneuvering near the frontline.
By late 2024, drones had become central to both sides’ strategies, compensating for deficits in manpower and artillery ammunition. The conflict evolved from artillery and mechanized formations to precision strike capabilities, electronic warfare, and drones. Ukraine’s will to fight and battlefield innovation proved critical, while Western support, though essential, often arrived poorly timed and at insufficient scale.
The Current Battlefield Dynamic
The current battlefield is characterized by porous lines, with Ukrainian forward positions separated by large gaps. Russian forces attempt to infiltrate these gaps, creating a “gray zone” of overlapping engagement zones roughly ten to twelve miles deep. This zone, dubbed the “kill zone,” is heavily saturated with strike and reconnaissance drones, making mechanized attacks difficult and infantry infiltration perilous. Amidst this deadlock, 2025 saw a struggle for superiority in the kill zone, with Russia expanding its drone formations and gradually shifting the zone more evenly across the battlefield, reducing Ukraine’s advantage.
The focus of fighting has shifted to drone units and artillery fire support. Ukrainian units report higher casualties among support and logistical positions than among combat infantry, leading to increased use of uncrewed ground vehicles for logistical roles and casualty evacuation. The expanding kill zone has also hindered force concentration. Both sides employ precision strike capabilities and one-way attack drones against high-value targets, with roads covered in counterdrone nets and vehicles equipped with electronic warfare systems.
Despite using small groups of infantry or lightly motorized troops to bypass Ukrainian positions, Russia has been unable to translate localized superiority into breakthroughs. Russian offensives have become a year-round slog, difficult to exhaust but unsuitable for rapid advances. Since 2024, Russian forces have been grinding their way along a 750-mile frontline, prioritizing the capture of the rest of Donetsk while simultaneously pursuing multiple axes of advance to pressure Ukrainian forces.
Territorial control is a lagging indicator of combat efficiency, and analysts disagree on how to assess it due to the prevalence of the gray zone. According to one measure, Russian forces advanced 1,930 square miles in 2025, compared to 1,620 square miles in 2024. However, these advances represent a small percentage of Ukraine’s territory, and capturing the rest of Donetsk would still require a lengthy and costly struggle.
Strike Campaigns and Economic Pressure
Both sides have expanded their strike campaigns against critical infrastructure. Russian strikes against Ukrainian infrastructure have intensified, particularly during the colder winter months, with rolling blackouts becoming common in Kyiv. Despite Western sanctions, Russia has increased production of missiles and long-range one-way attack drones. Ukraine has responded by targeting Russian energy infrastructure, disrupting refined fuel supplies and reducing Russia’s energy export revenues. Ukraine’s drone production is increasing, and strikes are beginning to impact Russian infrastructure.
Ukraine’s strikes aim to undermine Russia’s ability to sustain the war financially. Russia faces economic stagnation, a growing deficit, regional budget crises, and declining oil revenues. The pressure on Russia’s shadow fleet, used to evade sanctions, is increasing. While Russia is not on the verge of financial collapse, the economic foundations of its war effort are becoming increasingly shaky.
Challenges for 2026
Despite tactical adaptations, Russia’s combat efficiency is not improving. The Russian military is preserving equipment but suffering larger manpower losses. Recruitment rates are declining, and the quality of recruits is decreasing, leading to higher rates of desertion. While Russia still holds a manpower advantage, these negative trends are likely to worsen.
Ukraine faces challenges in maintaining combat strength at the front. Drone units often draw personnel from other areas, and replacing losses requires specialized training. Force management issues, including insufficient officers and equipment for new units, and a prohibition against retreat, hinder effective operations.
The war has taken on a regional character, with expanded attacks against commercial shipping and violations of NATO airspace. However, small changes can have ripple effects. Ukraine’s recent blocking of Russia’s access to Starlink could force a reorganization of Russian command and control.
In 2026, Ukraine will need to stabilize the frontline, address infrastructure vulnerabilities, and leverage drones and domestically produced cruise missiles to inflict greater economic damage on Russia. Russia’s prospects have not significantly improved, and economic strain is mounting. The key question is whether Russia’s offense or Ukraine’s defense is more sustainable. Time, increasingly, is not on Moscow’s side.
