images. In some situations, especially in free societies, it must be accepted that public buildings may always be subject to photography or other techniques. Countermeasures include putting visual shielding over sensitive targets or camouflaging them. When countering such threats as imaging satellites, awareness of the orbits can guide security personnel to stop an activity, or perhaps cover the sensitive parts, when the satellite is overhead. This also applies to imaging on aircraft and UAVs, although the more direct expedient of shooting them down, or attacking their launch and support area, is an option in wartime. Counter-OSINT While the concept well precedes the recognition of a discipline of OSINT, the idea of censorship of material directly relevant to national security is a basic OSINT defense. In democratic societies, even in wartime, censorship must be watched carefully lest it violate reasonable freedom of the press, but the balance is set differently in different countries and at different times. Britain is generally considered to have a very free press, but the UK does have the DA-Notice, formerly D-notice system. Many British journalists find that this system is used fairly, although there always be arguments. In the specific context of counterintelligence, note that Peter Wright, a former senior member of the Security Service who left their service without his pension, moved to Australia before publishing his book Spycatcher. While much of the book was reasonable commentary, it did reveal some specific and sensitive techniques, such as Operation RAFTER, a means of detecting the existence and setting of radio receivers. Operations Security Even though the principles of OPSEC go back to the beginning of warfare, formalizing OPSEC as a US doctrine began with a 1965 study called PURPLE DRAGON, ordered by the Joint Chiefs of Staff, to determine how the North Vietnamese could get early warning of ROLLING THUNDER fighter-bomber strikes against the North, and ARC LIGHT B-52 missions against the South. The methodology used was to consider what information the adversary would need to know in order to thwart the flights and the sources from which the adversary might collect this information. It became apparent to the team that although traditional security and intelligence countermeasures programs existed, reliance solely upon them was insufficient to deny critical information to the enemy—especially information and indicators relating to intentions and capabilities. The group conceived and developed the methodology of analyzing U.S. operations from an adversarial viewpoint to