In this paper presented at the first Korea-U.S. West Coast Strategic Forum, Daniel C. Sneider examines the state of the U.S.-ROK alliance in December 2006, two months after North Korea tested a nuclear device. While he downplays the notion that the alliance is “on the verge of collapse,” Sneider notes the strain placed on it by the differing perceptions in both countries of the threat posed by North Korea. He suggests a “re-imagining” of the alliance by elite U.S. and Korean opinion makers, and points to possible lessons to be drawn from the transformation of NATO after the Cold War.