WASHINGTON — In choice of both topic and foil, Rand Paul’s now legendary Senate filibuster was a stroke of political genius. The topic was, ostensibly, very narrow: Does the president have the constitutional authority to put a drone-launched Hellfire missile through your kitchen — you, a good citizen of Topeka to whom POTUS might have taken a dislike — while you’re cooking up a pot roast?

The constituency of those who could not give this question a straight answer is exceedingly small. Unfortunately, among them is Attorney General Eric Holder. Enter the foil. He told a Senate hearing that such an execution would not be “appropriate.”

Appropriate being a bureaucratic word meaning nothing, Holder’s answer was a PR disaster. The correct response, of course, is: Absent an active civil war on U.S. soil (of the kind not seen in 150 years) or a jihadist invasion from Saskatchewan led by the Topeka pot roaster, the answer is no.

The hypothetical being inconceivable, Paul’s performance was both theatrically brilliant and substantively irrelevant. As for the principle at stake, Holder’s opinion carries no weight in any case. He is hardly a great attorney general whose words will ring through history. Nor would anything any attorney general says be binding on the next president, or for that matter on any Congress or court.

The vexing and pressing issue is the use of drones abroad. The filibuster pretended not to be about that. Which is testimony to Paul’s political adroitness. It was not until two days later that he showed his hand, writing in The Washington Post, “No American should be killed by a drone without first being charged with a crime.” Note the absence of the restrictive clause: “on American soil.”

Now we’re talking about a larger, more controversial issue: the killing by drone in Yemen of al-Qaida operative Anwar al-Awlaki. Outside American soil, the Constitution does not rule, no matter how much Paul would like it to. Yet Paul’s unease applies to non-American drone targets as well. His quarrel is with the very notion of the war on terror, though he is normally too smart to say that openly and unequivocally. Unlike his father, who implied that 9-11 was payback for our sins, Paul the Younger more gingerly expresses general skepticism about not just the efficacy but the legality of the entire war.

That skepticism is finding an audience as the war grinds into its 12th year, as our hapless attorney general vainly tries to define its terms and as the administration conducts a major drone war with defiant secrecy. Nor is this some minor adjunct to battle — an estimated 4,700 have been killed by drones.

George W. Bush was excoriated for waterboarding exactly three terrorists, all of whom are now enjoying an extensive retirement on a sunny Caribbean island (though strolls beyond Gitmo’s gates are prohibited). Whereas President Barack Obama, with thousands of kills to his name, evokes little protest from yesterday’s touch-not-a-hair-on-their-head zealots. Of whom, of course, Sen. Obama was a leading propagandist.

Such hypocrisy is the homage Democrats pay to Republicans when the former take office, confront national security reality, feel the weight of their duty to protect the nation — and end up doing almost everything they had denounced their predecessors for doing. The beauty of such hypocrisy, however, is that the rotation of power creates a natural bipartisan consensus on the proper conduct of this war.

Which creates a unique opportunity to finally codify the rules. The war’s constitutional charter, the 2001 Authorization for Use of Military Force has proved quite serviceable. But the commander-in-chief’s authority is so broad that it has spawned suspicion, fear and now filibuster.

It is time to rethink. That means using the lessons of the last 12 years to rewrite the charter with a new code governing drone warfare and the question of where, when and against whom it should be permitted.

Necessity having led the Bush and Obama administrations to the use of near-identical weapons and tactics, a national consensus has been forged. Let’s make it open. All we need now is a president willing to lead and a Congress willing to take responsibility for the conduct of a war that, however much Paul and his acolytes may wish it away, will long be with us.