As Arab regimes struggle with demonstrations fueled by Twitter and Al Jazeera, and U.S. diplomats try to understand the impact of WikiLeaks, it is clear that this global information age will require a more sophisticated understanding of how power works in world politics.

Two types of power shifts are occurring in this century: power transition and power diffusion. The transition of power from one dominant state to another is a familiar historical pattern, but power diffusion is a more novel process. The problem for all states today is that more is happening outside the control of even the most powerful of them.

As for power transition, much attention nowadays is lavished on a supposed U.S. decline, often with facile historical analogies to Britain and Rome. But Rome remained dominant for more than three centuries after the apogee of its power, and, even then, it did not succumb to the rise of another state, but suffered a death by a thousand cuts inflicted by various barbarian tribes.

Indeed, for all the fashionable predictions that China, India or Brazil will surpass the United States in the coming decades, the greatest threats may come from modern barbarians and nonstate actors. In an information-based world of cyber-insecurity, power diffusion may be a greater threat than power transition.

What will it mean to wield power in the global information age of the 21st century? Which resources will produce power?

Every age produces its own answers. In the 16th century, control of colonies and gold bullion gave Spain the edge. Seventeenth-century Holland profited from trade and finance. Eighteenth-century France gained from its larger population and armies, and 19th-century British power rested on industrial and naval primacy.

Conventional wisdom has always held that the state with the largest military prevails. In an information age, however, it may be the state (or nonstate) with the best story that wins. Today, it is far from clear how to measure a balance of power, much less how to develop successful survival strategies for this new world.

Most current projections of a shift in the global balance of power are based primarily on one factor: projections of countries’ gross domestic product growth. They thus ignore the other dimensions of power, including both hard military power and the soft power of narrative, not to mention the policy difficulties of combining them into successful strategies.

States will remain the dominant actor on the world stage, but they will find the stage far more crowded and difficult to control. A much larger part of their populations than ever before has access to the power that comes from information.

Governments have always worried about the flow and control of information, and the current period is not the first to be strongly affected by dramatic changes in information technology. What is new — and what we see manifested in the Middle East today — is the speed of communication and the technological empowerment of a wider range of actors.

The current information age — sometimes called the “Third Industrial Revolution” — is based on rapid technological advances in computers, communications and software, which in turn have led to a dramatic fall in the cost of creating, processing, transmitting and searching for information of all kinds. And this means that world politics can no longer be the sole province of governments.

As the cost of computing and communication comes down, the barriers to entry decline. Individuals and private organizations, ranging from corporations to nongovernmental organizations to terrorists, have thus been empowered to play a direct role in world politics.

The spread of information means that power will be more widely distributed, and informal networks will undercut the monopoly of traditional bureaucracy. The speed of Internet time means that all governments will have less control over their agendas. Political leaders will enjoy fewer degrees of freedom before they must respond to events. They will then have to compete with an increasing number and variety of actors in order to be heard.

We see this as U.S. policymakers struggle to cope with today’s Middle East disturbances. The fall of the Tunisian regime had deep domestic roots, but the timing caught outsiders, including the U.S. government, by surprise. Some observers attribute the acceleration of the revolution to Twitter and WikiLeaks.

As the administration of U.S. President Barack Obama formulates policy toward Egypt and Yemen, it faces a dilemma. In Yemen, Ali Abdullah Saleh’s regime has provided important assistance in dealing with the threat from al-Qaida-affiliated terrorism. In Egypt, President Hosni Mubarak’s rule helped moderate the Israeli-Palestinian conflict and balanced Iranian power in the region. Simplistic endorsement of democracy by the administration of former U.S. President George W. Bush was costly both in Iraq and in Gaza, where elections gave rise to a hostile Hamas-led government.

In an information age, smart policy combines hard and soft power. Given what the United States is, the Obama administration cannot afford to neglect the soft-power narrative of democracy, liberty and openness.

Thus, Obama and U.S. Secretary of State Hillary Clinton have issued public as well as private appeals for reform and change in Egypt and the wider Arab world, while also urging limits to violence by all parties. Moreover, they have aligned themselves with freedom of information in the face of efforts by the Egyptian regime to block Internet access.

How events in the Middle East will play out is anyone’s guess, but in today’s information age, upholding the freedom to access information will be an important component of smart power.