North Korea threatens to attack U.S. on its own soil

Sometimes you hear some news, to digest them become another issue.....

Presently, North Korea leader has threatened to attack US if they continue with the annual military drill conducted in the Korean peninsula. Though, the greatly feared dictator really sees the drill also a threat to his own country, it should never amount to him bursting out with such heavy weight choices of words against the US. 

South Korea conducts the yearly exercises, called Ulchi Freedom Guardian, with the United States and other allies "to enhance ... readiness, protect the region and maintain stability on the Korean peninsula.

I remember so many threats from Saddam Hussein against US only find out he didn't have the such much acclaimed when US finally invaded the country. 

Or North Korea have some secret weapons the world do not know about???