In 1989 Moody’s downgraded Brazil to BB- unjustly, causing great problems and strife to the Brazilian citizen and government.
Moody’s and S&P, and most Americans, have yet to understand the concept of Real Interest rates, rather than Nominal Interest rates, which is a misleading pricing method. It misleads investors into believing that they are receiving significantly more "interest" than they really are. In Brazil that would be a against the law.
During the last twenty years, Brazil always had the ability to pay the Real Interest rate of its loans, plus an extra for amortization. It never deserved the rating of "questionable ability to pay".
Now a Brazilian Rating Company has used the reason against the US Treasuries. Since they are not indexed to inflation "there is a questionable doubt that investor’s will receive the true value of their investment, due to future US inflation".
For 30 year treasuries, where a 4% inflation will erode principal by 50% at least, a double CC would have been more justified. But that would have seemed overreacting.
But it is about time Americans realize that Nominal Interest Rates is a form of wrong measure, incorrect pricing model, since part of that interest is inflation, not interest. And inflation is not income by any means.
That is one the reason’s of the sub-prime crisis. Forcing poor people to pay "inflated interest rates" in the beginning of their life cycle, and paying totally eroded principal 30 years down the line.
Meanwhile inflation in Brazil is under control and Brazil today provides the highest real interest rate in the world which makes it a very interesting market for investments in and high yield bonds.