The separation of powers has spawned a great deal of debate over the roles of the president and Congress in foreign affairs, as well as over the limits on their respective authorities, explains this …

The Amazon Rainforest plays a critical role in global climate health, but accelerating deforestation continues to raise alarm. How are the region’s governments responding?

U.S. strategic and tactical nuclear weapons on land, in the air, and at sea, will undergo costly and extensive modernization in the coming years.