North Korea probably built it with parts acquired from all over, including the U.S.A., through some intermediary, and built some of them itself. You'll remember, perhaps, that Saddam got some of his WMDs from us (though they were gone before we invaded, as Bush "wagged the dog"). You'll perhaps remember also, that we got our technology from the Nazis. Those scientists had used doomed slave labor at Peenemunde to build their rockets. The loony Boy King has been working on this for a long time, following his dad and grandpa. Our own loony head of state is only marginally better, so don't count on him to not get us all killed. In fact, he is also a third generation sleaze. Anchorage is only 3,700 miles from Pyongyang, and Honolulu only 4,600 miles.  Our missile "defense," is notoriously ineffective, created mostly to make defense contractors rich, often helped by faked tests. Think Kodiak "spaceport" and the Ft. Greely anti-ICBM installation. It's all about pork.