I dont think America is going anywhere just yet. A recession, even one dragging on for 5 years will not end American power, or even change it in any meaningfull way. It will also harm the rest of the world, perhaps more than the US.
Were I to guess I would go for a double dip recession, with the stimulus package giving consumers a slight lift in the late summer\ early autumn. I also suspect the calls for the end of the recession will go on about every two weeks until it is over..... thats not a hard one, there were already a few articles saying the worst was behind us this week: then GE published its results and the markets took another shit. There is alot of capital (money) floating around the world looking for somewhere to be put to work. And I mean ALOT. Perhaps enough to cover for the losses in housing and investment instraments. Probibly not though. But at some point people will start looking for things to invest in and the US and world economy will lift up.
There are quite a number of longterm problems that will palgue the US for the next couple of decades, some like retirement of the largest section of there population will be problems every country faces, however it will hurt the US more than others due to the crazy cost of US health care which the state only has to cover once a person goes over a certain age (by and large there are exceptions). Europe Japan and China all face variations of this problem. Other problems like deficit spending are more unevenly spread, Japan being a significantly worse culprit that than the US in terms of the ratio between GDP and borrowing. And of course balance of trade where Germany is the worlds star, only last year did China finaly exceed the German balance of trade surplus in numbers, given the disparity between there populations it's a stunning insight into what a western economy can do if it is well managed.
America has alot of problems but so does everyone. The US still has the capacity to turn it around and use a big recession and a weak dollar to get back into manufacturing. It has the capital and the infrastructure to stay in the high end innovative manufacturing sector. A weak dollar may actualy kill Arianespace, Airbus and EADS.
But if we are looking at long term (decade and more) global power then there are two variables that are basicaly 90% of the game. Global warming and rescourse depletion. They are highly variable, high probability high impact variables.
India is rapidly running out of water. It relies heavily on water drawn from the water table and that is shrinking at an unsustainable speed. China and India also rely heavily on water from glacier melt for there great rivers, these glaceirs are slowly dissapearing. Over the next twenty years first India, then China are likely to run out of water and face famines. But before China faces famine it will hit problems keeping many of its factories and industries running due to water constraints. The increased likelyhood of droughts and other severe weather events are liable to create internal disturbances and even refeul civil violence and perhaps revolutionary armed struggle in both countries. I really cant see the Chindia phenomonem displacing the US as the worlds leading power.
In terms of resource depletion, my conservative estimate is that the world hits peak oil in 2011. There is so much obstification and outright lying about how much oil is available, but there are a host of new field (the socalled megaprojects) comming online between now and 2011 that they might be able to lift us above the 74.2 million barrels a day we achieved back in 2005.
This is recent world oil production (from Graphoilogy)
We have platued and the price of oil has shot through the roof
Now the growth in consumption in China and the asian tigers is burning out the ability of countries like Pakistan and Burma to buy oil, but once the oil starts depleating (as I and a number of other suggest it will; the big boys the governments and world energy bodies laugh of this suggestion) then the worlds power distribution will be by who can get enough oil to keep there economy going.
The US has 140 000 troops stood on Iraqi soil. China and the EU does not. The US has giant permenant bases in the UAE and Kuwait, China and the EU does not. I honestly believe the US wanted to turn Iraq into a stable liberal democracy (soft power is cheaper than hard power). I wholeheartedly believe that they were not out for plunder but to create a country that would gratefully allow them to remain (like Germany) and be an inspiration to the overthrow of the governments of Syria and Iran, that the spread of its values would cement the world together in a bond of shared love of freedom and liberal values. They just fucked up on a scale unseen since Barbarossa. But that aside they have the troops on the ground near the oil producers. No one else does.
America has its hands very firmly round the windpipe of every significant economy in the world. (except Russias).
Life for Joe 6 Pack may not be about to get better and even deteriorate over the next twenty years.
I just dont think the US's loss of influence will be to great over the next 5 years and I think that they will be back and growing as a power over the next ten to twenty years.