Now? or in 1953?
Most Americans don't realize that there is still a war going on! They think Koreans are on the brink of another Korean war.
However, the vast majority of Americans just don't know. they don't know what to think about it because they don't fully understand the situation.
i would say that the public opinion is that "Kim Jong-il is bad and he should be stopped" but that is as far is it goes, because no one knows how or when it would even be possible without massive casualties in the south.
also most peeps think that kim is his first name :P