While it is impossible to predict with absolute certainty my opinion is that North Korea likes to threaten with nuclear attack using it to intimidate others but will not actually follow through with that threat. The casualties that would be brought upon the North Koreans themselves by stronger nations would be huge.
North Korea is not likely to launch a nuclear attack against a superpower such as the United
States. The country has made a lot of threats, especially in light of increased sanctions. However, if North Korea were to launch an attack, it would face massive casualties from its better armed adversaries.
Launching a nuclear attack is a useful threat, but the reality is that any actual attack made on a superpower would result in an attack by that superpower, and likely other nations, on North Korea. That might result in some serious damage to the Superpower but would result in the total destruction of North Korea. Only someone who had lost their mind or was in a position of absolute hopelessness would actually attack a Superpower with nuclear weapons.
No, I do not think North Korea is going to launch a nuclear attack against a world superpower in the near future because North Korea understand that launching an attack would spell doom for the country's dictatorship. I believe that North Korea boasts about its military efforts to intimidate other nations and also to show their nation's citizens that the country is a great nation.