Issued by whom?
<pedant mode> A number of PPRuNe posters and news outlets have said that Trump has issued an emergency order. Perhaps I'm not reading the right news, but I see only that Trump has said that "we" and "the FAA" will issue an emergency order, and I see that the FAA has said, "The FAA is ordering the temporary grounding of Boeing 737 MAX aircraft..." - no emergency order from the White House per se. </pedant mode>