To implement this covert program, the administration has adopted a tool that lowers the threshold for lethal force by reducing the cost and risk of combat. This still-expanding counterterrorism use of drones to kill people, including its own citizens, outside of traditionally defined battlefields and established protocols for warfare, has given friends and foes a green light to employ these aircraft in extraterritorial operations that could not only affect relations between the nation-states involved but also destabilize entire regions and potentially upset geopolitical order.

Hyperbole? Consider this: Iran, with the approval of Damascus, carries out a lethal strike on anti-Syrian forces inside Syria; Russia picks off militants tampering with oil and gas lines in Ukraine or Georgia; Turkey arms a U.S.-provided Predator to kill Kurdish militants in northern Iraq who it believes are planning attacks along the border. Label the targets as terrorists, and in each case, Tehran, Moscow, and Ankara may point toward Washington and say, we learned it by watching you. In Pakistan, Yemen, and Afghanistan.

This is the unintended consequence of American drone warfare. For all of the attention paid to the drone program in recent weeks—about Americans on the target list (there are none at this writing) and the executive branch’s legal authority to kill by drone outside war zones (thin, by officials’ own private admission)—what goes undiscussed is Washington’s deliberate failure to establish clear and demonstrable rules for itself that would at minimum create a globally relevant standard for delineating between legitimate and rogue uses of one of the most awesome military robotics capabilities of this generation.