Edward Horgan, a well-known Irish activist and former Irish Defense Force officer, has had his 10-year, multiple-entry U.S. visa revoked without explanation. Horgan and others believe it is because of his principled stand against the U.S. use of renditions, and in particular, the use of Shannon Airport in western Ireland as a stopover for U.S. rendition flights. The Obama administration should be ashamed for its behavior in keeping Mr. Horgan from entering this country.