Drones, however, present none of these issues. There is nothing novel or unusual about the destructive potential of a drone strike.

Pretty much every weapon in the U.S. arsenal may be used in war, provided the users (1) have the legal authority to use them, (2) aim them at that legitimate targets, and (3) use them according to the rules of engagement laid out by their commanders. All those bases are covered when it comes to drones.

Congress has given the commander-in-chief an Authorization to Use Military Force--AUMF in Washington-speak--and that's all the legal authority he needs. And, as Mark Bowden's article in this month's The Atlantic illustrates well, the administration has plenty of rules for running armed drone operations.

Here is the brutal reality of war: It always requires targeting enemies with lethal force. It is an operational necessity. And it is legal.

The problem some people have with killer drones in combat has little to do with the technology of flying weapons. As my colleague at Heritage, Cully Stimson testified before Congress, "Much criticism of drone warfare is actually criticism of broader policies, such as the application of the law of armed conflict to the present conflict, geographical limitations on such conflict, and targeting decisions. Whether a strike is carried out by a drone or an airplane (with the pilot in the vehicle itself) has little or no bearing on these broader policy issues."

Turning drone strikes into a battle of legal briefs is more an act "lawfare" than warfare--an attempt to hamstring U.S. military operations by clothing complaints in legal-sounding arguments. Amnesty International declared in its 2012 report that U.S. operations do not "recognize the applicability of international human rights law," an assertion the report conclusively fails to document. Christof Heyns, the UN special rapporteur on extrajudicial killings and summary or arbitrary executions, stated at a conference in Geneva that some U.S. operations might constitute "war crimes." Though he has been on the job for many months, he has yet to prove that allegation.

To recapitulate: President Obama has the right to drone on as long as the authority of the AUMF remains in force and as long as he operates within that authority (or operates under some other legal authorization for the use force).

That said, it must be noted that the president's way of drone warfare makes little sense. Forget about the lawfare challenges. In going forward with its drone wars, the White House faces at least four big problems for which it has no good answers.

First, the drone war isn't working. The threat posed by al Qaeda and its affiliates--both in their operational capacity to keep targeting the West and in their efforts to destabilize countries in the Middle East and North Africa--continues to grow despite the drone campaign. Obama is battling a global Islamist insurgency with a flyswatter. He likes to say we're winning, but in reality we are losing ground.