[Billthedrill]

IF there were a test and IF it was successful, the Japanese knew about it when it happened.

[Bobby777]

IF there were a test and IF it was successful, the Japanese knew about it when it happened.

we would too ... from the ground sensors, to sniffers in spy planes to satellites if they were dumb enough to do it under clear skies ...

[r9etb]

IF there were a test and IF it was successful, the Japanese knew about it when it happened.

Yes. And they also knew better than to take it upon themselves to address the situation. I have no doubt that we, SK, and Japan have been coordinating closely on this.