Poll results from South Korea's Chosun Ilbo:

A recent [South Korean] survey asked people which country they believes most threatens [South] Korea's security. 33 percent named North Korea, and 39 percent named the United States. Among people in their twenties, 58 percent said the U.S. was the bigger threat, while only 20 percent cited the North. If we were to act upon the results of that survey, then the U.S. should be considered the Republic of Korea's main adversary, instead of North Korea.