Isolating North Korea

So apparently, in Washington, they think that North Korea will become further isolated if it conducts planned nuclear testing.

You know, far be it from me to be too critical when I have no politically acceptable proposed alternatives (my own proposal of just taking out all their military installations in a single massive overnight strike not being very popular apparently), but would someone kindly explain to me just how possible it would be to isolate North Korea more than it already is? Carve the entire nation out of the Earth’s crust and put it into orbit? Relocate it to the moon perhaps?

I’m serious. Someone, tell me how you “further isolate” North Korea. I’m dying to know.