Was it effective for President Biden to warn Russia without stating the exact consequence?
Short answerYes; strategic ambiguity deters while preserving options and avoids committing the United States to one automatic response.
NotesAn unspecified warning leaves room to tailor consequences to the action actually taken. The adversary knows escalation will carry a cost without being told exactly how to plan around it. A precise red line can box a government into a response it later judges disproportionate. Strategic ambiguity therefore preserves deterrence while reducing the risk that leaders feel compelled to use nuclear weapons merely to uphold their own wording.