As of today, US is not having bit of problem generating debt for its expenses at extremly trivial costs compared to what the emerging markets might be giving. Just go and check the returns on 1yr, 3yr, 10yr and 30yr UST bills.
Considering the balance sheet of US, pundits have started the raga of announcing that the UST is a grand bubble so start shorting it. In a way they are right, but what is the right moment to short the Treasury bubble?
What happens, when countries like China and Japan stop financing the US debt? It may be of importance if we just look at the strong winds of change in the baby boomers generation in US. There are enough indicators by the investment gurus well versed with the situation, that now baby boomers might turn to a savings oriented community rather than consumption oriented. So the savings rate are going to provide US government a sizeable proportion of the reserves making their life bit not much easier, but still it would help.