My guess is that the editorial writers have never actually read the relevant article of the conventions, but instead have simply relied on press releases from various rights groups that tell the WaPo what it wants to hear. . . .
The point, then, is that the Post editorial repeats a error oft-heard across MSM, that by failing to provide individualized hearings, the US is in violation of the Geneva Conventions. As a policy matter, and indeed as a matter of basic fairness, it should do so. As a matter of international law, that, I'm afraid, amounts to a MSM urban legend.
I can't say I find this surprising. Anderson is quite critical of the Bush Administration's stance as a matter of policy, but notes that it is nonetheless not a violation. In too many minds, however, the Conventions are simply a wish-fulfillment tool, or a slogan.