If they are in a foreign country beyond the reach of conventional American law enforcement capabilities and are operating as a senior member of Al Qaeda or an associated force planning to kill other Americans. Such strikes would have to take place in accordance with applicable law of war principles (ie. the Geneva Conventions).

Yup. Sounds about right to me. What's the big deal with the Obama administration killing traitors who have pledged allegiance to a genocidal hate-filled terrorist movement, again? Would the bandana-wearing peace faction like to explain how the alternatives of waiting for these barbarians to attack us, or going in with a full-scale boots-on-the-ground intervention that will kill lots more people, are preferable to drone strikes?