The United States' leading intelligence organisation has warned that the world is entering an increasingly unstable and unpredictable period in which the advance of western-style democracy is no longer assured, and some states are in danger of being "taken over and run by criminal networks".

The global trends review, produced by the National Intelligence Council (NIC) every four years, represents sobering reading in Barack Obama's intray as he prepares to take office in January. The country he inherits, the report warns, will no longer be able to "call the shots" alone, as its power over an increasingly multipolar world begins to wane.

Looking ahead to 2025, the NIC (which coordinates analysis from all the US intelligence agencies), foresees a fragmented world, where conflict over scarce resources is on the rise, poorly contained by "ramshackle" international institutions, while nuclear proliferation, particularly in the Middle East, and even nuclear conflict grow more likely.

"Global Trends 2025: A World Transformed" warns that the spread of western democratic capitalism cannot be taken for granted, as it was by George Bush and America's neoconservatives.

"No single outcome seems preordained: the Western model of economic liberalism, democracy and secularism, for example, which many assumed to be inevitable, may lose its lustre – at least in the medium term," the report warns.

It adds: "Today wealth is moving not just from West to East but is concentrating more under state control," giving the examples of China and Russia.

"In the wake of the 2008 global financial crisis, the state's role in the economy may be gaining more appeal throughout the world."

At the same time, the US will become "less dominant" in the world – no longer the unrivalled superpower it has been since the end of the Cold War, but a "first among equals" in a more fluid and evenly balanced world, making the unilateralism of the Bush era no longer tenable.

The report predicts that over the next two decades "the multiplicity of influential actors and distrust of vast power means less room for the US to call the shots without the support of strong partnerships."

It is a conclusion that meshes with president elect Obama's stated preference for multilateralism, but the NIC findings suggest that as the years go by it could be harder for Washington to put together "coalitions of the willing" to pursue its agenda.

International organisations, like the UN, seem ill-prepared to fill the vacuum left by receding American power, at a time of multiple potential crises driven by climate change the increasing scarcity of resources like oil, food and water. Those institutions "appear incapable of rising to the challenges without concerted efforts from their leaders" it says.

In an unusually graphic illustration of a possible future, the report presents an imaginary "presidential diary entry" from October 1, 2020, that recounts a devastating hurricane, fuelled by global warming, hitting New York in the middle of the UN's annual general assembly.

"I guess we had it coming, but it was a rude shock," the unnamed president writes. "Some of the scenes were like the stuff from the World War II newsreels, only this time it was not Europe but Manhattan. Those images of the US aircraft carriers and transport ships evacuating thousands in the wake of the flooding still stick in my mind."

As he flies off for an improvised UN reception on board an aircraft carrier, the imaginary future president admits: "The cumulation of disasters, permafrost melting, lower agricultural yields, growing health problems, and the like are taking a terrible toll, much greater than we anticipated 20 years ago."

The last time the NIC published its quadrennial glimpse into the future was December 2004. President Bush had just been re-elected and was preparing his triumphal second inauguration that was to mark the high-water mark for neoconservatism. That report matched the mood of the times.

It was called Mapping the Global Future, and looked forward as far as 2020 when it projected "continued US dominance, positing that most major powers have forsaken the idea of balancing the US".

That confidence is entirely lacking from this far more sober assessment. Also gone is the belief that oil and gas supplies "in the ground" were "sufficient to meet global demand". The new report views a transition to cleaner fuels as inevitable. It is just the speed that is in question.

The NIC believes it is most likely that technology will lag behind the depletion of oil and gas reserves. A sudden transition, however, will bring problems of its own, creating instability in the Gulf and Russia.

While emerging economies like China, India and Brazil are likely to grow in influence at America's expense, the same cannot be said of the European Union. The NIC appears relatively certain the EU will be "losing clout" by 2025. Internal bickering and a "democracy gap" separating Brussels from European voters will leave the EU "a hobbled giant", unable to translate its economic clout into global influence.

Disaster diary

An imaginary diary entry written by a future US president, produced to illustrate a climate-change disaster:

Those images of US aircraft carriers evacuating thousands in the wake of flooding stick in my mind. Why must the hurricane season coincide with the UN general assembly in New York?

It's bad enough that this had to happen; it was doubly embarrassing that half the world's leaders were here to witness it. I guess the problem is we had counted on this not happening, at least not yet.

• Read the full National Intelligence Council global trends review (pdf)