When the leaders of NATO nations gather in Lithuania this week, President Biden and his closest allies will endeavor to send Russia a forceful message: that the West is united against Russian President Vladimir Putin's war in Ukraine.
But jeopardizing their show of cohesion will be several of the same leaders joining Biden for the Vilnius summit, whose refusal to admit Sweden as the 31-nation bloc's newest member underscores the divisions that could erode NATO's deterrent power amid a dangerous standoff with Moscow.