You can look at the military radio log yourself.
http:// www.eam.watch/log
It is believed that the messages type "SKYKING" pertain to US military forces that are nuclear-armed.
The remaining messages, type "RADIO CHECK" or "ALLSTATIONS", pertain to other US military forces.
These are coded. We cannot know the meaning. All we can do is count the messages and compare with the usual number on other days.