It's been four long years since the full-scale Russian invasion of Ukraine. Four years of

suffering for Ukraine's people, four years of stubborn resistance from Ukraine's military forces,

fighting to defend their homeland.

The obvious question now is whether Vladimir Putin actually believes that he is leading Russia

to a military victory, or simply relying on Trump administration pressure on Ukraine's president

Vladimir Zelensky to win at the negotiating table what Russia has failed to win by force of arms.

Either way, what does this long-drawn-out conflict tell us about Russia and Putin himself?

A failed leader steering a declining superpower?

Or someone of infinite cunning and cruelty who may yet claim to make Russia great again?

I'm Gavin Esler, and this is not a drill. Samuel Green worked and lived in Moscow for more than a decade and is currently professor in Russian politics at King's College London. Good to talk to you, Sam.

Good to be with you. Sam, let's start with the big picture. I mean, four years on from this

full-scale invasion, can you give us your assessment of where things are on the battlefield first?

Well, I mean, things on the battlefield are where they have been from the vast majority of this

war, which is, you is dug in, moving ever so

slightly in one direction or another. Russia is making moderate progress here and there, right,

but only moderate progress really in the context of this war. And they're paying a tremendous

price in terms of manpower to make that progress.

It's not making a serious dent in Ukraine's ability to defend itself, which of course does not

mean that it's not doing tremendous amounts of damage to Ukraine. So what we have seen, in fact,

is that most of the damage that Russia has been doing particularly over the last

six months or so really has been nowhere near the front line. It has not even been designed

to make it difficult for Ukraine to maintain its defenses on the front line. It's been designed

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