No one knows how many names are on the no-fly list. According to one source, 21,000 people, including some 500 Americans, are blacklisted; another puts the figure at 44,000. The actual number is classified.
For almost a decade the U.S. government refused to let Stanford Ph.D. student Rahinah Ibrahim back in the country after putting her on a no-fly list and not telling her why. Invoking the state secrets privilege, Attorney General Eric Holder claimed the information she wanted “could reasonably be expected to cause significant harm to national security.”