I haven't seen this list referenced by the administration as the rationale, but the list of countries is the same as those included in a question added to the E

I haven't seen this list referenced by the administration as the rationale, but the list of countries is the same as those included in a question added to the Electronic System for Travel Authorization (ESTA) application in June 2016, which addresses countries DHS considers at higher risk: Have you traveled to, or been present in, Iraq, Syria, Iran, Sudan, Libya, Somalia, or Yemen on or after March 1, 2011? https://www.cbp.gov/travel/international-visitors/visa-waiver-program/visa-waiver-program-improvement-and-terrorist-travel-prevention-act-faq https://www.cbp.gov/travel/international-visitors/visa-waive... Please note that I really don't understand the details of the visa process in general or this program in particular, or how DHS arrived at this list of countries. I'm just submitting it as an pre-existing list of countries the DHS has expressed concern about with respect to immigration and visas. Nor do I have any reference that this list was used for the Executive Order. That said, it does seem reasonable to imagine that similar reasoning was used in choosing the countries listed in the Executive Order.