They are building up resentments in other countries that will last for generations. I guess that's all right with them, as long as they keep profiting now.
Ultimately, the value of our bonds will be determined by the strength of our military. As long as we remain able to crush all opposition into dust, they will retain some value. When and if we lose the ability to directly influence world affairs, then some catalyst will occur - like the Fall of Taiwan - that will show the world once and for all that we are a paper tiger. Then, Obama will feel his "revenge" - many times over.
Like you, I think this is quite a few years off yet. Japan-style deflation without Japanese societal cohesiveness is our immediate future. Things will just keep gradually getting worse, as they have since 2006.
Ever heard of Kyle Bass? If not, Google him. He has actually MADE $$ from these various bubbles, and as such has more credibility than some others (like Peter Schiff or Rick Santelli). In any case, I urge you to give this video a watch. Its long, but extremely educational and compelling.
http://www.youtube.com/watch?v=JUc8-GUC1hY