It's the Korean harvest festival holiday Oct. 5-9. 추석; 秋夕; lit. 'autumn eve.' Big holiday in South Korea 15th day of the 8th lunar month. Variations of the holiday are celebrated in the other East Asian countries.

The story below on the US SSBN missile launches in September was just published, I believe by Simone Chun. As far as I know these launches are unprecedented. Usually, I thought they'd launch just one as a test exercise. Looks like it drew a reaction in North Korea.

North Korea is playing the Long Game and has scored a significant victory against the US. Trump is ill suited to be running US foreign policy at this time. Any competent leader would understand the situation and negotiate a face-saving long term treaty for peace on the Korean peninsula. Instead, Trump is blustering and threatening and in the long run will have to declare bankruptcy, screw his creditors and claim victory... as usual.