If NK is serious about sinking a US aircraft carrier what's the best way for them to do it?

[astro]

Given their known resources if the NK forces determined they wanted to sink an US aircraft carrier what is their best shot at doing so using existing hardware?

I do remember several years ago a Chinese electrically powered sub popped up in the middle of US carrier fleet exercises and surprised them so it’s not like our detection abilities are infallible.

The uninvited guest: Chinese sub pops up in middle of U.S. Navy exercise, leaving military chiefs red-faced

North Korea says it is ready to strike U.S. aircraft carrier

North Korea remained defiant.

“Our revolutionary forces are combat-ready to sink a U.S. nuclear-powered aircraft carrier with a single strike,” the Rodong Sinmun, the newspaper of the North’s ruling Workers’ Party, said in a commentary.

The paper likened the aircraft carrier to a “gross animal” and said a strike on it would be "an actual example to show our military’s force

[beowulff]

http://boards.straightdope.com/sdmb/showthread.php?t=824615