But after the Kremlin's initial limited successes, the volume and effectiveness of cyber operations fell away, according to Western experts.

As the war dragged on, Russian hackers were unable to compensate for failures on the battlefield -- not least because of the support Ukraine has received, including in cyberspace.

"One of the things that it [the war] has demonstrated is that when you have a coalition, a group of not only state and non-governmental actors, but also the commercial sector really trying to come together and provide defense in depth -- this war has really shown that there's a lot of power in that kind of coalition," Gavin Wilde, senior fellow in the Technology and International Affairs programme at the Carnegie Endowment for International Peace, told Euronews.

According to Kyiv, Moscow tries to back up almost any military strike with attacks on digital infrastructure.

But according to experts, the effectiveness of the hackers' operations is dependent upon success on the battlefield. Cyberwars alone are not enough.

"Despite talking about it [cyber warfare] for 30 years, this is the first time you've been able to see in real time how cyber contributes to an overall military campaign," Dr Tim Stevens, Senior Lecturer in Global Security at King's College, London, told Euronews. "Yes, it can be useful under certain circumstances, but it's not going to win you a war".

Battle for public opinion

One area where Moscow has spectacularly failed is in the battle for public opinion in the West.

Amid the casualties and destruction caused by Putin's troops and missiles, experts such as Gavin Wilde say the cyber war has receded into the background.

"Certainly technology is very expensive, but brutality is very cheap. And so this war in particular, I think, has reminded us of the central role of humans and the human aspect of warfare," he said.