A representative argument from Bradbury

If you believe this was offered in good faith, I've got a bridge to sell you. It's taken from Section II.B of Bradbury's 30 May 2005 memo.

As a condition to its advice and consent to the ratification of the CAT, the Senate required a reservation that provides that the United States is

bound by the obligation under Article 16 to prevent "cruel, inhuman or degrading treatment or punishment," only insofar as the term "cruel inhuman or degrading treatment or punishment" means the cruel unusual and inhumane treatment or punishment prohibited by the Fifth, Eighth, and/or Fourteenth Amendments to the Consitution of the United States.

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Conceivably, one might read the text of the reservation as limiting only the substantive (as opposed to the territorial) each of the United States obligations under Article 16. That would not be an unreasonable reading of the text. Under this view, the reservation replaced only the phrase "cruel, inhuman or degrading treatment or punishment" and left untouched the phrase "in any territory under its jurisdiction," which defines the geographic scope of the Article. The text of the reservation, however, is susceptible to another reasonable reading--one suggesting that the Senate intended to ensure that the United States would, with respect to Article 16, undertake no obligations not already imposed by the Constitution itself. Under this reading, the reference to the treatment or punishment prohibited by the constitutional provisions does not distinguish between the substantive scope of the constitutional prohibitions and their geographic scope. As we discuss below, this second reading is strongly supported by the Senate's ratification history of the CAT.
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The Supreme Court has repeatedly suggested in various contexts that the Constitution does not apply to aliens outside the United States. See, e.g., United States v. Belmont, 301 U.S. 324, 332 (1937)("[O]ur Constitution, laws, and policies have no extraterritorial operation, unless in respect to our own citizens."; United States v. Curtiss-Wright Export Corp., 299 U.S. 304, 318 (1936) ("Neither the Constitution nor the laws passed in pursuance of it have any force in foreign territory unless in respect of our own citizens...."; see also United States v. Verdugo-Urquidez, 494 U.S. 259,271 (1990) (noting that cases relied upon by an alien asserting constitutional rights "establish only that aliens receive constitutional protections when they have come within the territory of the United States and developed substantial connections with this country"). Federal courts of appeals, in turn, have held that "[t]he Constitution does not extend it guarantees to nonresident aliens living outside the United States," Vancouver Women's Health Collective Soc'y v. A.H. Robbins Co. 820 F 2d 1359, 1363 (4th Cir. 1987); that "non-resident aliens...plainly cannot appeal to the protection of the Constitution or laws of the United States," Pauling v. McElroy, 278 F.2d 252,254 n.3 (D.C. Cir. 1960) (per curiam); and that a "foreign entity without property or presence in this country has no constitutional rights, under the due process clause or otherwise," 32 County Sovereignty Comm. v. Dep't of State, 292 F.3d 797, 799 (D.C> Cir. 2002) (quoting People's Mojahedin Org. of Iran v. Dept of State, 182 F.3d 17, 22 (D.C. Cir. 1999)).
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The reservation required by the Senate as a condition of its advice and consent to the ratification of the CAT thus tends to confirm the territorially limited reach of U.S. obligations under Article 16. Indeed, there is a strong argument that, by limited the United States obligations under Article 16 to those that certain provisions of the Constitution already impose, the Senate's reservation limits the territorial reach of Article 16 even more sharply than Article 16 standing alone. Under this view, Article 16 would impose no obligations with respect to aliens outside the United States. And because the CIA has informed us that these techniques are not authorized for use against the United States persons, or within the United States, they would not, under this view, violate Article 16.

Schematically:

1. Article 16 of the Convention Against Torture prohibits signatories from engaging in "cruel, inhuman or degrading treatment or punishment."

2. When ratifying the CAT, the Senate attached a legally binding reservation specifying that "cruel, inhuman or degrading treatment or punishment" as referenced in the treaty meant just those cruel, unusual, and inhumane treatments which would be prohibited by the Fifth, Eighth, or Fourteenth amendments.

3. While one could, conceivably, take this reservation to apply to the question of what kinds of treatments amount to "cruel, inhuman or degrading treatment or punishment", it is more reasonable to interpret the reservation as limiting the scope of the CAT so that the US did not, by signing the CAT, undertake any obligations which were not already narrowly specified by the Fifth, Eighth, or Fourteenth amendments.

4. Constitutional protections, including those of the Fifth, Eighth, and Fourteenth amendments, apply only to U.S. citizens and (some) resident aliens; aliens outside of U.S. territory do not have constitutional protections.

5. In signing the CAT, the United States did not undertake any obligations not to engage in "cruel, inhuman or degrading treatment or punishment" of aliens so long as such treatment or punishment takes place outside of U.S. territory.