The massive network of defenses has weaknesses, according to military experts who described Russia’s preparations, but it is already slowing offensive operations and creating bottlenecks for the Ukrainian army, forcing it to try to break through on narrow paths, which allows Russia to regroup and aim more precisely.

“They’ve had months to create a defensive plan, they’ve dug in and used the terrain, they’ve been sitting there for six months laying little traps and mines,” said Dara Massicot, an expert on the Russian military at Rand Corp. “They feel as confident as they are probably going to feel that they understand their defensive lines.”

More than a week after the start of Ukraine’s much-hyped counteroffensive, which Kyiv and its Western supporters say will push the Russian invaders back to preinvasion lines, there are signs that Ukraine is unlikely to achieve lightning gains as it did last fall in the northeast Kharkiv and southern Kherson regions.

So far, Ukraine has claimed advances covering little more than 40 square miles of territory. However, Russia occupies more than 800 times that amount, roughly 33,000 square miles. About half of that territory was seized before the February 2022 invasion, including Crimea and parts of Donetsk and Luhansk regions.

Some analysts, and even some members of the Ukrainian military, believe that Kyiv has yet to unleash its full counteroffensive and is holding back most of its attack brigades.

Even if that is true, other experts say Russia’s military failures last year created a misperception of weakness. Offensive operations are far more difficult and attacking armies suffer far more casualties than the defending side. Now, last year’s roles are reversed with Ukraine trying to attack.

“The Russians are fighting on well-prepared positions and have accumulated a sufficient amount of artillery ammunition, plus they have more drones, and in this aspect, at the moment, they are no worse than the Armed Forces of Ukraine,” said Russian military analyst Ian Matveev.

Russia has built so many fortifications that it does not even have enough troops to deploy along all of its defensive lines, analysts say. Mazes of trenches and obstacles, including cement antitank pyramids called dragon’s teeth, are concentrated in the Zaporizhzhia region, which is a key axis for Ukraine’s counterattack.

A sea of land mines is also scattered across southeast Ukraine.

“There are so many minefields in front of positions and many kilometers away from them, on the roads, in the fields, and it’s really difficult,” Massicot said. “And a lot of Ukrainian breaching equipment has been destroyed already, so trying to cut through all these mines is a real challenge. That’s the first line of defense.”

Then come the drones. Pro-war Russian bloggers and reporters have gleefully posted video clips of Lancet drones smashing Western materiel on a near-daily basis over the past two weeks. Lancets are a Russian-made loitering munition effective against artillery systems, light armored vehicles and some tanks.

Two clips, purporting to show Lancets damaging a prized IRIS-T air defense system and a coveted Leopard 2 tank provided to Ukraine by Germany, sent Russian state media into a frenzy.

“Light, fast, quiet and precise, the Lancet gets the credit for dozens of hit targets in the special military operation zone,” a report aired by Russian Channel One said last week.

According to LostArmour, a pro-Kremlin project that compiles geolocated videos and photos of Lancet attacks, Russian forces have increased use of the self-detonating drones and staged at least 33 attacks this month. “They can drive them in and drop them on a vehicle and disable it,” Massicot said.

“We are seeing more of that recently,” she added. “Their counter battery has improved in terms of the rate that they can make decisions and target Ukrainians.”

Russia and Ukraine have each struggled with depleted stocks of artillery munitions. Russia has been saving up shells, which was likely behind a conflict between the regular military and Wagner mercenary boss Yevgeniy Prigozhin, who accused the Defense Ministry of denying his fighters needed ammunition.

Russian forces are also using aviation more actively. Dozens of videos shot from helicopters have been leaked to pro-war Russian bloggers since the counteroffensive started.

One clip trumpeted by the Defense Ministry as a successful strike on a Leopard tank turned out to be video of a destroyed combine harvester, according to several pro-Russian military bloggers, but other geolocated clips show successful hits on Ukrainian vehicles.

More decisive, close-in attacks are a significant change in aviation tactics compared to previous months, when attack helicopters mostly fired afar, avoiding Ukrainian front line air defenses, said Pavel Aksenov, a Russian military reporter and expert with the BBC’s Russian service.

Aviation support is a weak spot for Ukraine, with Ukrainian President Volodymyr Zelensky pleading from the outset for F-16 jets. President Biden decided last month to allow allies to supply the planes but it will take months to train Ukrainian crews to operate them.

“Though Russia has quantitative superiority in air power and artillery — with Ukraine actively trying to degrade the latter — Moscow lacks manpower, arms, commanders and a sustainable, efficient command structure,” Pavel Luzin, a military expert at the Jamestown Foundation, said in a recent analysis.

Speaking with Russian military reporters last week, President Vladimir Putin boldly asserted that Ukraine’s combat losses were “ten times higher” than Russia’s casualties, without providing evidence.

Still Russia’s forces seem to present a weak spot.

“The units … in operation right now, I don’t want to call them healthy, I’d say they are in okay shape,” Massicot said. “They’ve stuffed them with mobilized folks with variable training.”

Moscow in recent months appeared to tighten its command structure and discipline, which seemed to be in chaos for much of last year. Since fall, Valery Gerasimov, chief of the general staff, has led the overall war effort and offensive operations to little success. But his subordinates — Gen. Sergei Surovikin and Col. Gen. Mikhail Teplinsky — appear to have patched up some initial flaws and managed to boost morale in some key forces, like the airborne troops.

“Some units in Zaporizhzhia are really focused,” Massicot said. “I don’t see panic anywhere on the Russian lines.”

Defense Minister Sergei Shoigu has also attempted to assert firmer control over mercenaries and “volunteer battalions” by forcing them to sign official army contracts, though internal disagreements persist.

By Putin’s own admission, a shortage of weapons and equipment, especially strategically crucial arms like long-range missiles, Orlan drones, and tanks, presents another problem for Russia. Moscow has procured drones from Iran and various components from China, but the supply does not match the military aid Ukraine has received from Western countries.

“There is a lot that we need,” Putin told military reporters recently before claiming that Russia has massively ramped up production. “For the main types of weapons, our production for the year increased by 2.7 times. And as for the most in-demand items, it’s tenfold!”

Luzin cast doubt on this alleged increase, saying that based on Russian government statistics, “it is hard to see how Russian arms manufacturing could have increased ‘by many times’ in these industries over the past year.”

Massicot noted that Russians are worried about Ukraine’s ability to fight at night due to better thermal optics, which the Russians lack. This has prompted family members of some Russian soldiers to seek donations for night vision systems.

Analysts interviewed by The Washington Post said it’s too early to make any predictions about the outcome of the counteroffensive as the Ukrainian army is still facing its main test: breaking through to Russian lines and persevering in large-scale infantry fighting.

“There’s a theory that if Ukrainian forces come into contact with actual Russian soldiers, they’ll have another Kharkiv-like collapse,” Massicot said. “Russia doesn’t want to take that bet. So their goal is to keep them as far away as possible with mines and artillery strikes.”