Since it was first rolled out a week ago, Trump's travel ban has been evolving - both because of legal challenges and as a result of decisions by the administration to walk back aspects of it. Green-card holders from the affected countries, for example, no longer need waivers to get into the United States, as they did when the order took effect. And the Department of Homeland Security asserted Friday that the order does not apply to dual citizens with passports from countries other than the seven listed.