In the aforementioned video, Senator Paul pointedly asked Senator McCain whether McCain-Levin would permit the president to designate an American citizen as an enemy combatant and ship him to Gitmo for indefinite detention. The Arizonan wouldn’t (couldn’t?) answer the question, mumbling something about public opinion. But the question deserves an answer.

Ever since Congress authorized combat operations in 2001, the president has been permitted to treat American citizens as enemy combatants. Such treatment has been exceedingly rare, affecting only four Americans over the course of ten years: Yasser Hamdi, who was captured in Afghanistan; Jose Padilla, who was captured in Chicago; and Anwar al-Awlaki and Samir Khan, who were killed two months ago in a drone strike in Yemen. This paltry number owes to the fact that, contrary to demagogic suggestions by Paul and Napolitano, the president is not free, willy-nilly, to designate just anyone, including political adversaries, as an enemy combatant. Instead, the designation may be applied only to citizens who satisfy the aforementioned statutory definition of an enemy combatant: participation in 9/11 or abetting the alien enemy factions (al-Qaeda, the Taliban, and their affiliates) expressly targeted by Congress.

Could a president abuse such power? Of course — all power can be abused. McCain-Levin, however, does not make such abuse any more likely than it was before McCain-Levin. More to the point, presidents are highly unlikely to abuse this particular power given that (a) they take an oath to uphold the law, (b) the political downside of intentionally using war powers to abuse Americans, an impeachable offense, would be devastating, and (c) detainees have lavish due-process rights to challenge their designation, so an abusive designation would inevitably result in a court order vacating the designation and directing the prisoner’s release.

Paul’s fretting over American enemy combatants’ potentially being shipped off to Gitmo is also misplaced. The whole point of choosing Gitmo as a detention site was to thwart any argument that federal courts had jurisdiction to intrude. The detention camp is intended for alien enemy combatants only. The degree to which American citizens maintain their constitutional protections outside U.S. territory is an open question, and thus detaining Americans at Gitmo would invite the courts to do exactly what the executive branch wants to forefend: interfere in wartime detention matters. That is why Yasser Hamdi was instantly transferred out of Gitmo when it was learned that he was an American citizen. And it is noteworthy that, while Gitmo was fitted with courtrooms for the conduct of military-commission trials, our law does not authorize such trials for American citizens — it was assumed that citizens would not be detained or tried at Gitmo.