For more than a week, Samiullah Naderi, a U.S. legal permanent resident, waited days and nights with his wife and son outside the airport in Kabul, Afghanistan, hoping to be let in so that they could leave on one of the dozens of daily flights headed to America.

For two days, Aziz Shinwari has been fielding frantic calls and online messages from relatives in Afghanistan, trying to help get them out of the country.