the initial security briefing. Dual citizenship Dual citizenship is associated with two categories of security concerns: foreign influence and foreign preference. Dual citizenship in itself is not the major problem in obtaining or retaining security clearance in the United States. If a security clearance applicant's dual citizenship is "based solely on parents' citizenship or birth in a foreign country", that can be a mitigating condition. However, exercising (taking advantage of the entitlements of) a non-U.S. citizenship can cause problems. For example, possession and/or use of a foreign passport is a condition disqualifying from security clearance and "is not mitigated by reasons of personal convenience, safety, requirements of foreign law, or the identity of the foreign country" as is explicitly clarified in a Department of Defense policy memorandum which defines a guideline requiring that "any clearance be denied or revoked unless the applicant surrenders the foreign passport or obtains official permission for its use from the appropriate agency of the United States Government". This guideline has been followed in administrative rulings by the Department of Defense (DoD) Defense Office of Hearings and Appeals (DOHA) office of Industrial Security Clearance Review (ISCR), which decides cases involving security clearances for Contractor personnel doing classified work for all DoD components. In one such case, an administrative judge ruled that it is not clearly consistent with U.S. national interest to grant a request for a security clearance to an applicant who was a dual national of the United States and Ireland. DOHA can rule on issues involving the granting of security clearances. United Nations The UN has a Security Clearance (SC) procedure and document for United Nations staff travelling to areas designated as security phase areas, with numbers ranging from one to five ("no-phase" areas are calm countries where no SC is required). United Nations staff can apply for SC online, at the website of the Department for Safety and Security. Individuals who have had security clearances revoked In the post World War II era, there have been several highly publicized, and often controversial, cases of officials or scientists having their security clearances revoked, including: John O. Brennan (claimed but not processed) Sandy Berger Rod Blagojevich John M. Deutch Thomas Andrews Drake Abdel-Moniem El-Ganayni Michael T. Flynn Wen Ho Lee Robert Oppenheimer Aldric Saucier Edward Snowden Alan Turing (UK) Qian Xuesen This list does not cover people whose security clearance lapsed possibly following changing their