Poland has become the first allied state to publicly treat a reduced or uncertain American role in NATO as a scenario that must be taken seriously. While France pushes for greater European responsibility, the United Kingdom is strengthening its continental strategic footing, and the Baltic states are already thinking in worst-case terms, Romania is quietly broadening its options without openly invoking a Plan B. The deeper shift is not yet legal, but strategic and psychological: Europe is entering an era in which the American guarantee can no longer be treated as an unquestioned certainty.