But what about the yield on the bonds? 
Japan has less than 1% rates while the U.S. has 5% 
So the interest on the new and renewing debt is going to be much higher on the U.S. debt. 

if inflation stays and rates don't go down (what Jamie Dimon indicated yesterday on Bloomberg) I think the dollars demise will occur much faster inside 5 years for sure. 

The interest on the debt is already 1.1 trillion with only collecting 4.5 trillion in tax