Reince Priebus is now on record as saying that the order
does not apply to green card holders going forward.
https://www.nytimes.com/2017/01/29/u...be-barred.html
UK foreign secretary Boris Johnson has been told by the US government that the order only applies to people who
departed from the 7 countries. Someone traveling from another country (eg UK) would be not be subject to the ban, even if they hold citizenship from one of the 7 countries.
https://www.gov.uk/government/news/p...igration-to-us
However, anyone who has traveled to or holds citizenship to one of the 7 countries, should expect some extra scrutiny at the US border.
The executive order itself was very vague and enforcement depends heavily on the interpretation by individual immigration officers as well as DHS as a whole. Unfortunately many green card holders and people not departing from the 7 countries have faced issues entering the US in the past few days. Hopefully there will be less confusion soon as things are clarified by the government.