The debt is unsustainable.
Try this:
Nonsense. Debt owed to the public, the only debt we actually have to service to avoid default, is only 60% of GDP. History proves that countries can manage that kind of a debt burden without any trouble for extended periods of time.
What is unsustainable is Social Security and Medicare. But these programs be modified by statute, their benefits reduced to make them sustainable.
The doom and gloom you are preaching is neither rational nor productive.