US still hopes for the 'conversion' of North Korea?

During the post ww2 years, the reactionary pope Pius xii urged his faithful to pray for the conversion of Russia and all the countries that had fallen under its long, Communist shadow.
When it comes to North Korea, the US and its North Korean clerisy walk in the path Pius trod. And they have spectacularly failed: North Korea has not imploded; it has not collapsed; it has not had an epiphany to see the error of its ways, repent, and convert to American style 'democracy'.
You would think with a path of failure, the US and its talking heads, advsiors, ivy leagued ph.d.s, slush funded foundations and think tanks would take a different tack. GuamDiary had alerted its readers of the single minded pursuit of the blind hound that is US policy in its blog on Victor Cha's opinion piece in the 'Financial Times of London'.
You may scratch your head as to the drop of US policy that triggered the DPRK testing of a nuclear device. There's no need to dwell long on the cause: look at George W. Bush's 'principled', kick 'em in the labonza' approach to North Korea. And boy did he and his minions backpaddle fast. Saying this, like thee Bourbons, Bush & Obama for that matter, have learnt nothing in elaborating a 'realistic' North Korea policy: they have learnt nothing,forgotten everything!