A formal entity called the United States with structure derived from its constitution? Could be a thousand years.
My pet theory is that the US will eventually go the way of the HRE. Just like there was an emperor, there's going to be a president in Washington DC for centuries to come. He's going to be a very important person who'll have soldiers in fancy uniforms saluting him, but the centre of real political power will have moved somewhere else.
Gotta define collapse.
The domestic system of governance? Already collapsing.
The ability of the state to project military power? A decade or two for most of the world, an extra decade for South America.
A formal entity called the United States with structure derived from its constitution? Could be a thousand years.
My pet theory is that the US will eventually go the way of the HRE. Just like there was an emperor, there's going to be a president in Washington DC for centuries to come. He's going to be a very important person who'll have soldiers in fancy uniforms saluting him, but the centre of real political power will have moved somewhere else.
Like boardrooms?
It already has! It was always there!
And I just thought about Rome again