France, Feb. 24 -- Four years after Russia launched its full-scale invasion of Ukraine, Europe's largest conflict since the Second World War grinds on - reshaping the continent's security order while exacting a staggering human toll. Wtih the war entering its fifth year on Tuesday, there is little indication that a decisive end is near, despite renewed diplomatic efforts.

Talks brokered by the United States, part of the Trump administration's year-long push for peace, have brought delegations from Moscow and Kyiv to the table. Yet fundamental disagreements - over the fate of Russian-occupied territories and Ukraine's long-term security guarantees - continue to block meaningful progress.

On the battlefield and far beyond it, the cost of ...