I hooked up Fiddler the other day to do some run of the mill testing and I started seeing these requests...
I shut down the browsers and continued to see this request periodically. I pulled up the URL in a browser and got nothing. It would seem to be a continual polling performed by Windows to see if the government has anything to say in which case what happens? Would a dialog box pop up? Would you see an amber alert or a public service announcement warning about something dire? Is it more like an amber alert for cyber attack information? Would Windows do something like lock down ports or respond in some remote-controlled manner like an anti-botnet?
I'll continue to look into this and see what I can find.