On the eastern edge of NATO's territory, Lithuania is quietly transforming its borderlands into a landscape of deterrence — digging, building, and training against the possibility that history might repeat itself. A nation of fewer than three million people, wedged between Russia and its Belarusian ally, has concluded that the distance between worst-case planning and present-day necessity has collapsed. What unfolds along these flat, unguarded frontiers is an old human question rendered urgent again: whether the visible will to resist is enough to make violence too costly to begin.