Don or Hillary-In a few months one of you will be President. How'd you like to face this scenario: North Korea now has nukes they can launch from submarines. Since their subs are old and noisier than my dad's old Buick, our Navy knows where they are. Our Navy's very good.

Suppose one of them is in international waters off the West Coast, armed and ready to launch at Seattle, San Francisco, Los Angeles, or even little Portlandia. You'll know this because our spies are also good.
What are you going to do, Mr. or Madam President?

You know there's no point in talking to the North Korean leadership since they are all insane. Do you sink the boat? BTW that's an act of war and always has been. And since they likely have more than one, how many are you going to sink? And can you get them all? And what if you do get lucky and get them all, then heck: those psychopaths can just launch from their homeland and hit Japan, Hong Kong, The Philippines, etc.. The missiles don't even have to be accurate-there's no such thing as a "near miss" with a nuclear strike.
Ok, Donald or Hillary: Your call. You wanted to be President. In the movies it only takes a few keystrokes for a happy ending. How about this time?