Analysis: How Western allies are strengthening Ukraine's defence against Russian invasion

When the Russian invasion of Ukraine began in February 2022, Ukraine's military fought back with the equipment it had on hand: Soviet-era aircraft, tanks, armoured vehicles and artillery, and a scattering of Western-supplied weapons such as Javelin anti-tank missiles.

Within weeks, shipments of military support from Ukraine's allies began to arrive and helped bend the trajectory of a war that already seemed to be going badly for the Russian military.

"You could make an argument for the March 22 security assistance package that included Javelins and other anti-tank munitions" as being one of the highest-impact arms shipments of the war, said Ankit Panda, a Stanton Senior Fellow at the Carnegie Endowment for International Peace.

In the months after, artillery ammunition came, then Western artillery and vehicles. Then in June, HIMARS arrived. The rocket artillery vehicles - the High Mobility Artillery Rocket System - carry munitions that can hit a target a few metres in diameter from distances of nearly 80 km (50 miles). Almost immediately, Russian command centres and supply depots far behind the front lines were hit.

"HIMARS was not really a capability Ukraine had before," said Rob Lee, a senior fellow at the Foreign Policy Research Institute. "Russia wasn't able to adjust. It obviously had a big impact in that first month."

Western countries have in the first weeks of 2023 pledged heavy armour, such as modern tanks, and rocket-launched glide bombs - Ground-Launched Small Diameter Bombs (GLSDB) that can hit small targets up to 150 km (93 miles) away.

Since the opening months of the war, Ukraine has reclaimed large swathes of territory in its south and east. As Ukrainian forces advanced, a growing list of Western-provided weapons have made a difference on the battlefield.

"All weapon systems we provide Ukraine are important - not just the shiny big-ticket items," said George Barros, an analyst at the Institute for the Study of War.

"The small arms the U.S. and others sent Ukraine in early 2022 helped kit out Ukraine's territorial defence forces, which were important in helping arm organised civilian militias to defend Ukraine's large cities ...There's a value added for every weapon that goes to Ukraine."


The U.S. and Western allies have provided Ukraine with about two dozen vehicles that can fire Guided Multiple Launch Rocket System (GMLRS) missiles, which are directed to their targets via GPS programming.

The vehicles, known as M142 and M270 in the U.S., are wheeled and tracked vehicles, respectively, that can move much faster than conventional artillery and can launch all of their missiles in a matter of minutes after arriving at a firing point.

The M142, known as HIMARS, has drawn the most attention, as it can travel up to 85 kph (53 mph), allowing it to quickly move out of range of any attempts to attack it after it fires its rockets.

Analysis: How Western allies are strengthening Ukraine's defence against Russian invasion
Photo credit: Reuters

The GMLRS rounds transferred to Ukraine have a range of about 100 km and an accuracy of a few metres.

"HIMARS is highly survivable," Panda said. "HIMARS systems have been able to relocate after firing rapidly, as the system is designed to do. If you look at the total capability ... relative to the number delivered, HIMARS has had an outsized effect."

Self-propelled artillery

Western self-propelled artillery - cannons mounted on tracked or wheeled platforms that can move themselves from place to place - began arriving in Ukraine in summer 2022.

All of the systems use 155mm shells, which is the NATO standard. The most prominent: M109, AS90, CAESAR, PzH2000, Krab, Zuzana 24 and Archer.

Analysis: How Western allies are strengthening Ukraine's defence against Russian invasion
Photo credit: Reuters

There are many differences among the systems, but their common traits, besides ammunition type, are that they are mobile, carry their own ammunition and have computerised aiming.

They all can use 155mm GPS-guided shells, dubbed Excalibur, which extend the range of the cannons and allow the rounds to land in an area as small as 3 metres. All told, Ukraine has received more than 150 such weapons.

"Traditionally in war, artillery is the greatest casualty-producing weapon," Lee said. "We often focus on more high-tech things, but artillery, they call it the king of battle. It plays a key role in wars, particularly large land wars."

Wheeled artillery

Much more numerous than self-propelled artillery are cannons that are towed by trucks or other heavy vehicles.

The most numerous Western systems donated to Ukraine are the M777 and M119 (designated the L119 in Britain). The M777 is a 155mm gun that can fire GPS-guided shells and has a range of up to 40 km (25 miles), depending on what type of ammunition is used.

The guns are relatively easy to emplace and relocate, and like other supplied equipment, move Ukraine to NATO-standard ammunition.

Analysis: How Western allies are strengthening Ukraine's defence against Russian invasion
Photo credit: Reuters

The M119/L119 is a 105mm howitzer with a range of about 18 km (11 miles), designed to be moved and fired faster than larger weapons. Their relatively light weight--2,000 kg (4,500 pounds) or so--means they can be towed by pickup truck. Both types have been provided to Ukraine in the hundreds.

"The first 155mm NATO howitzers, without them they would have had fewer artillery to use and they would have been able to fire far fewer artillery rounds," Lee said. "The howitzers were better than what Ukraine had before. But one of the main benefits was they brought along a new source of ammunition. That has been critical to allowing Ukraine to sustain this war."

Armored vehicles

As Ukraine has undertaken counter offensives that have recaptured large amounts of territory, it has needed large numbers of vehicles to move infantry.

Ukraine already operated many Soviet-vintage vehicles of this type, but since mid-2022, its Western allies have donated hundreds more, including M113, Marder, Bulldog, Bradley and Stryker vehicles.

Some are tracked and some use wheels; more advanced types such as the Marder, Bulldog, Bradley and Stryker also include useful sensors and aiming equipment such as thermal optics.

They are designed to withstand strikes from small arms and some light anti-tank weapons, and support infantry with weapons of their own ranging from .50 calibre machine guns to 25mm autocannons and guided anti-tank missiles.

"The bigger issue than tanks has been a lack of armoured personnel carriers," Lee said of Ukraine's forces. "I think that actually might be more important because there is a bigger demand or bigger need."

"The relative improvement in capability of a Bradley over a BPM-1 (Soviet-era armoured personnel carrier) is greater" than that of a Western tank over what Ukraine operates now, he added.


The government of Ukraine has consistently asked its allies for tanks. Some, such as Poland, provided surplus Soviet-era gear such as T-72s.

But in January, Britain pledged to send 14 Challenger 2 tanks--current-generation systems that the British military fields in its army. The Challenger 2 uses a diesel engine, making it familiar for Ukraine's forces to maintain, is about 50% heavier than a T-72 and is much more heavily armoured. It can reach speeds of about 60 kph (37 mph) on roads.

Although it uses a NATO-standard calibre for its main gun--120mm--the Challenger 2's barrel is rifled, unlike the smoothbore weapons used in other Western tanks. That means it uses unique ammunition, which Britain will also provide.

The United States has also pledged dozens of advanced Abrams tanks, which are powered by gas turbine engines, and other allies have promised to deliver modern German-made Leopard 2 tanks.

Analysis: How Western allies are strengthening Ukraine's defence against Russian invasion
Photo credit: Reuters

"Western states' provision of main battle tanks to Ukraine will help enable Ukraine to conduct mechanised warfare to defeat the Russian military and liberate Ukrainian territory," Barros said.

"Tanks play an important role in combined arms warfare by giving forces manoeuvrable armoured firepower. Tanks are not obsolete, and Ukraine will need these and even more tanks to break through Russian lines."

Air defence

Ukraine's civilian infrastructure, including power plants and residential buildings, have come under increasing attack from Russian missiles and one-way drones, often launched from outside Ukraine's territory.

To help defend against such attacks, its Western allies have donated a wide variety of systems. They range from short-range heat-seeking systems such as the Humvee-mounted Avenger to the high-end, radar-guided Patriot, which can engage aircraft, cruise missiles and ballistic missiles.

Medium-range systems such as NASAMS and IRIS-T provide a means of defending against missiles as they get closer to their targets.

As a last ring of defence, German Gepard anti-aircraft cannons, which are directed by radar and mounted on a tracked vehicle, can shoot down stragglers at relatively low cost. Ukraine's government has said these guns have been particularly valuable in defending against Iranian-made one-way attack drones, which are small and slow.

Analysis: How Western allies are strengthening Ukraine's defence against Russian invasion
Photo credit: Reuters

"The fact that the Russians were never able to suppress Ukrainian air defences was another thing that surprised analysts early in the war," Panda said. "The Russians got very little juice for their squeeze in terms of their ability to change the battlefield with (ballistic and cruise) missiles. So eventually we began to see more indiscriminate use."

Anti-ship missiles

In 2022, Ukraine used its indigenously made Neptune anti-ship missiles to sink Russia's Black Sea flagship, the cruiser Moskva. Since then, Denmark has donated Harpoon anti-ship missiles and shore-based launchers.

The Cold War-era missiles are relatively simple by modern standards but extend the range at which Ukraine can hold Russian ships at risk.


Ukraine has received millions of rounds of ammunition, including artillery shells. Some of these shells have advanced capabilities, such as the Excalibur, which uses GPS guidance and steering fins to hit targets as small as 3 metres from up to 40 km away.

Ukraine has also received BONUS and SMArt 155 rounds, which deploy submunitions that float down under parachutes or small wings, hunting for the infrared signatures of armoured vehicles. When one is spotted, the submunition waits until it is aimed properly, then fires a shaped charge into the top of the target.

Ukraine has also been provided with HARMs--High Speed Anti-Radiation Missiles--which it has rigged to fire from its Soviet-era aircraft to attack Russian air-defence radars.

"If it hadn't been for artillery ammunition, they would have been in a lot of trouble," Lee said. "Precision-guided munitions mean you have to fire fewer rounds. The ability to destroy targets on a first strike is a really important advantage."

Access to allies' intelligence has also helped Ukraine on the battlefield, Lee and Panda said. Knowing when Russia might strike, or where vulnerable supply depots might be, have helped Ukraine weather the invasion, which Russia calls a "special military operation", and continue to fight, they said.

In providing a $2.5 billion aid package in January, U.S. Secretary of State Antony Blinken said the weapons and supplies were crucial to "support Ukraine as it bravely defends its people, its sovereignty and its territorial integrity". NATO Secretary General Jens Stoltenberg echoed those comments in a speech in late January, saying: "Our support is making a real difference for the Ukrainians. Helping them not only to survive, but also to push back the Russian invader, and liberate their territory."

Russian officials say Western shipments of arms to Ukraine show that the U.S.-led NATO military alliance is fighting against Russia. Russia says any Western arms delivered to Ukraine are legitimate targets and President Vladimir Putin has warned the West that its leaders are deeply mistaken if they think they can defeat Russia.

"By helping Ukraine, the West is pursuing its own selfish goals," said Maria Zakharova, Russia's foreign ministry spokeswoman. "All deliveries of weapons to Kyiv are paid for with the blood of ordinary Ukrainians who are driven to the front to protect the financial interests and geopolitical aspirations of the United States and its allies."

Ukrainian President Volodymyr Zelenskiy has said the Western weapons and supplies have been vital to his country's ability to fight the Russian invasion.

"Russia wants the war to drag on and exhaust our forces," he said in January. "So we have to make time our weapon. We have to speed up events, speed up supplies and open up new weapons options for Ukraine."

Panda noted that regardless of the shipments of weapons, Ukraine's military success could not be attributed to any one system. Its military has simply performed well.

"Before the war broke out ... the majority of analysts did not think the Ukrainians would fight as well as they did," he said. "There is no sort of 'one weird trick' the Ukrainians have relied on to succeed."

By Gerry Doyle, Anurag Rao and Vijdan Mohammad Kawoosa