Do you think we will see the Fed go to negative int rates

I think it is a real possibility

If the Fed doesn't go negative then the USA will have the majority of non negative new bond issues in the world, assuming current trends continue

The last thing the USA economy wants is a stronger USD and higher int rates vs the rest of the world, are a big reason why off shore money will flood the USA bond market 

Investment wants yield and if the USA is the best yield, investors will follow the yield

IMHO this woud not be good