Default in such a large country is impossible, it has many allies and creditors who will help prevent this. A lot of things revolve around the United States, and such a default takes place only if it is, as you wrote, technical. In fact, it doesn't mean anything and it doesn't make sense to move from place to place and so on.
Every country is in economic turmoil, no one will go out of their way to save the US. The only savior will be who it is in debt to, the banking sector. Once the banking sector takes over the country, the country will become like a top-down managed business. Everything will be controlled, managed, tightened to be maximal efficiency for their interests, for production, for profit. The livestock (people) will serve no other purpose than to serve the interests of its new god-like leader.
This might sound ridiculous to some, however it is the message in all dystopian novels and films from decades ago til now. That's the fate of the US. How it will effect other countries is yet to be discovered.