Estimates of the total long-term economic costs of the Iraq and Afghanistan wars vary wildly and remain hotly disputed among experts.

With U.S. forces mired in Iraq, the cost of war has escalated. But some critics decry the manner in which the war is being funded more than the price tag itself.

Damage to Japan’s Fukushima Daiichi nuclear power plant has reignited debate over the safety of nuclear power and highlighted questions over aging power plants, safety procedures, and waste disposal…

The scramble for energy alternatives has brought new focus on nuclear power in the United States, but its revival faces political and practical obstacles.

Backgrounder: U.S. debate over treatment of detainees hinges on interpretation of the Geneva Conventions.