The presence of armed drones is a reality of the modern battlefield, but only a limited group of countries has the technological ability to produce them or the military capacity to operate them. The United States once held the edge in drone development and use, but as more countries gain access to the technology, armed drones have entered a new stage of proliferation. From the perspective of the United States and others, this proliferation is dangerous. Attempts to curb the spread of armed drones are becoming more difficult now that the United States is no longer their sole developer. China, in particular, has grown as a global exporter of unmanned combat systems, and other countries are planning to follow suit.