ISIS isn't a geographically defined area or political entity. Even if I was to agree with you that nuking things makes them go away. You would be nuking a number of countries and most of isis would just be fine. Nukes aren't used because they mainly affect civilians and not the people you are aiming to kill. It worked in WWII because Japan is a country and countries tend to not like their civilian population to be decimated so they surrendered. The US had nothing close to the arsenal necessary to wipe Japan off the map and that was not the plan. Hiroshima and nagasaki were dissuasive but that would not work against isis and would play right in their hands because of all those children and sisters and fathers you killed. You would essentially be giving a reason to become terrorists for generations to come. It is exactly the opposite that we should be doing. Look what was done with the Germans and Japanese or chinese Make your enemies your trading partners and subversively become mutually dependant. Boom no more foreign terrorism. Now if people would just stop bombing their own countries!

Nuking north Korea is stupid and the result would be a lot of US hate. NK will unravel over time and they are no threat to the us so nukes are pointless.