supreme.justia.com/cases/federal/…
(See, e.g., repository.law.umich.edu/cgi/viewconten…)
But what's especially vexing is how lower courts have subsequently _extended_ it, like the DC Cir. in Saleh:
pacer.cadc.uscourts.gov/internet/opini…
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The more interesting question is which areas, and why.
/end