Clean-energy technology is expensive and the United States is spending far too little on developing it.

Governments across the Middle East and South Asia are increasingly losing power to substate actors that are inserting themselves at a mezzanine level of rule between the government and the people.

The United States worldwide system of more than 1,000 military bases, stations, and outposts has actually provokes conflict and creates insecurity.

Moscow would like to trade its cooperation on a range of international issues for technology and investment, both of which it needs for domestic growth and stability.

Americans must realize that expanding educational attainment everywhere is the best way to grow the pie for all.

The ouster of General Stanley McChrystal does not suggest that U.S. political-military relations are in crisis. But the episode should remind the military's highest officers of the need for, and the requirements of, appropriate professional behavior.

President Obama must recognize that there is not a clean divide between a moderate pro-American camp and an extremist militant axis and take into account the Middle East's rapidly shifting dynamics.

In Reset, Stephen Kinzer argues that the United States should partner with Iran and Turkey to promote democracy and combat extremism in the Middle East. Although it is hard to imagine Iran as a friend of Washington, Turkey is ready to play that role.

The Pentagon recognizes the catastrophic threat posed by cyberwarfare, and is partnering with allied governments and private companies to prepare itself.

In The Flight of the Intellectuals, Paul Berman argues that it is not violent Islamists who pose the greatest danger to liberal societies in the West but rather their so-called moderate cousins, such as Tariq Ramadan.

David Remnick's The Bridge delivers fresh insights about Barack Obama's personal and political odyssey -- particularly when it comes to understanding the degree to which Obama is a product of New England's commitment to social and global reform.

Jane Burbank and Frederick Cooper's extensive volume and Timothy Parsons' selective survey are systematic treatments of empires; Richard Immerman's history is a focused critique of America's imperial career. None is an apologia for the United States.

Despite international pressure, Iran appears to be continuing its march toward getting a nuclear bomb.

The U.S. government must improve its ability to help its partners defend themselves or, if necessary, fight alongside U.S. troops.

After World War II, "trading states" seemed to be charting a new path forward. But small was not beautiful. Even great powers found themselves negotiating larger markets through economic associations with others. It's time the United States became such a power.

Washington's approach to rebuilding economies devastated by conflicts and natural disasters is flawed.

The era in which U.S. foreign policy could be driven in counterproductive directions by an excess of power is in the process of ending.

The United States' mission in Afghanistan will not be accomplished until a central government exists there that can control the country's territory.

U.S. President Barack Obama has vocally promoted a human rights agenda. Now, his administration must translate his rhetoric into practice.

Imperial collapse may come much more suddenly than many historians imagine. A combination of fiscal deficits and military overstretch suggests that the United States may be the next empire on the precipice.