Ahh, I really appreciate it when someone writes a well-written, level-headed argument that I disagree with. It feels less common in slashdot these days.
I'd first ask, do visa holders who were affected by the EO have constitutional rights, specifically the right to due process? If so, does an EO ostensibly about foreign policy render the EO unreviewable despite the clear fact that it tramples on the due process rights of visa holders?
I believe the answer to the first question is emphatically yes and the jurisprudence I'm aware of around this question suggests that USSC has established this as precedent. For example, Zadvydas_v._Davis. As to the 2nd question, I'm not aware of anything in the constitution to suggest the president is able to override due process rights and therefore the order is reviewable in the specific. Nor is there any part of the constitution that says the president is able to label executive orders as foreign policy orders in order to escape constitutional review.
More broadly, it seems like quite a blank check to issue to state the executive can merely ascertain on its own that its orders are about foreign policy and therefore unreviewable or that if there is a foreign policy element, as adjudicated by the courts, then other constitutional concerns are rendered irrelevant and the judiciary must consider the order unreviewable. Basically, while I agree the executive should have broad discretion with respect to foreign policy, they shouldn't be allowed to revoke visas, once given, without due process; which was the affect of the order.