Russia’s invasion of Ukraine four years ago launched Europe’s biggest conflict since World War II, causing immense suffering for civilians and harrowing ordeals for soldiers while rewriting the post-Cold War security order . The fighting enters its fifth year on Tuesday, and it shows no signs of stopping any time soon. The U.S. has brokered talks with delegations from Moscow and Kyiv as part of the Trump administration’s yearlong push for peace . But reconciling key differences , such as the