The fact that our NIS Director has been banned from entering the US...

We can't know for sure because the US isn't saying anything, but
it seems like our country has violated something.
That's why they are making Korea sit out this cyber response meeting regarding North Korea,
and they say they will restrict North Korea-related information moving forward.
I suspect that our country might have provided information to North Korea.
The reason they are excluding us from the North Korea cyber response meeting
might be because they're afraid the meeting contents will be leaked to North Korea...
The fact that the US is acting in a way they haven't before suggests something is up.