With regard to Chief Judge Sentelle's question about whether, under the plaintiffs' theory, the federal courts were "unconstitutional" until Congress conferred general federal question jurisdiction in 1875, of course not. The problem is that Chief Judge Sentelle thereby assumes that, without general federal question jurisdiction, there couldn't have been damages relief against federal officers (and so Congress crosses no constitutional line by foreclosing such jurisdiction today). This is simply not the case. Indeed, it's well established that, for the better part of the first 150 years of the Republic, damages remedies against federal officers invariably arose under common law, and were often pursued in state--rather than federal--courts. (There's a lot of good scholarship on this point; for starters, interested readers should check out Ann Woolhandler's exhaustive article on The Common Law Origins of Constitutionally Compelled Remedies, 107 Yale L.J. 77 (1997).) Moreover, as Professor Woolhandler (among others) has explained these cases often ended up in federal court anyway before 1875, either because the plaintiff invoked diversity jurisdiction (which does date to the Founding), or because the defendant invoked the federal officer removal statute (a variant of which was on the books as early as 1815).
Thus, with all due respect to Chief Judge Sentelle, the real question is not whether federal question jurisdiction was available in the federal courts for a damages claim against federal officers; it's whether any judicial forum was available for such a claim. Clearly, the answer was yes. And because courts have construed the exclusivity provisions of the 1988 Westfall Act as ousting state courts of the power to entertain tort claims against federal officers acting within the scope of their employment, today, that traditional avenue appears to no longer be available. That's why it really is Bivens or nothing for plaintiffs in cases like Al-Zahrani. (And why Congress thereby triggers a previously unanswered constitutional question when it takes away jurisdiction over such claims without providing an alternative remedy.) Reasonable minds may differ about how that question should be answered, but my point yesterday was merely that, to date, the Supreme Court hasn't weighed in.
As for Judge Randolph's question about the law of the D.C. Circuit, I don't disagree, although I'd put the point somewhat differently. Whether the plaintiffs in fact have the constitutional rights at issue in a Bivens suit does not usually go to the existence of a cause of action, but rather to whether the officer defendants are entitled to qualified immunity (indeed, that was the basis for the dismissal in Rasul I, and one of the two bases for dismissal in Rasul II). So to my mind, the more relevant precedent on whether a Bivens claim is available is not Kiyemba (as Judge Randolph suggested), but rather the second holding in Rasul II, i.e., footnote 5's conclusion that "special factors" cut against inferring a Bivens remedy in Guantanamo cases. Whether I like it or not (I've suggested elsewhere that such reasoning is problematic), Rasul II certainly is the law of the circuit (as evidenced by the court's reliance on it to dismiss Bivens claims by non-citizens formerly detained in Iraq and Afghanistan in the Ali case). That's why, as I suggested yesterday, my brief is not with the result in Al-Zahrani, but the (novel) reasoning.
Even if no Bivens claim is available here, and even if Congress could therefore validly divest the federal courts of jurisdiction over this Bivens claim, it is something else altogether to hold that damages suits are never constitutionally required. That's what's new--and, to my mind, alarming--about yesterday's decision.