Russia has massed 190,000 troops along its border with Ukraine—enough, according to analysts, to undertake the largest military land operation in Europe since 1945. Ukraine’s generals acknowledge that their military could be overwhelmed by a Russian invasion. But some Ukrainians—including great grandmothers, teenagers, advertising executives, and others—have been quietly preparing to resist. These unlikely civilians practice with prop guns and purchase their own rifles. They have pursued combat-skill classes and hands-on training in private and government-run programs.