Editing Strategic Defense Initiative (section)

===Lead up to SDI===
{{main|X-ray laser}}

[[Image:Tumbler_Snapper_rope_tricks.jpg|thumb|upright=1.0|The bright spikes extending below the initial fireball of one of 1952's [[Operation Tumbler–Snapper]] test shots, are known as the "[[rope trick effect]]". They are caused by the intense flash of ''thermal''/[[soft X-rays]] released by the explosion heating the steel tower guy-wires white hot. The development of the [[W71]] and the [[Project Excalibur]] x-ray laser were based on enhancing the destructive effects of these x-rays.]]

[[George Shultz]], Reagan's [[Secretary of State of the United States|secretary of state]], suggested that a 1967 lecture by physicist [[Edward Teller]] was an important precursor to SDI. In the lecture, Teller talked about the idea of defending against nuclear missiles using [[nuclear weapon]]s, principally the [[W65 (nuclear warhead)|W65]] and [[W71]], with the latter an enhanced thermal/X-ray device used on the [[LIM-49 Spartan|Spartan missile]] in 1975. Held at [[Lawrence Livermore National Laboratory]] (LLNL), the 1967 lecture was attended by Reagan shortly after he became governor of California.<ref name=gps>{{Cite book |last=Shultz |first=George Pratt |authorlink=George P. Shultz |url={{google books|plainurl=yes|id=96LVnQEACAAJ|page=261}} |page=261|title=Turmoil and Triumph: My Years as Secretary of State |date=1993 |publisher=Scribner's |isbn=978-0-684-80332-6 |language=en}}</ref>

Development of [[laser weapon]]s in the [[Soviet Union]] began in 1964–1965.<ref>{{cite web|url=http://www.fas.org/spp/starwars/program/soviet/990600-bmd-rus.htm|work=[[Nevsky Bastion]]|publisher=Federation of American Scientists|author=A. Karpenko|title=ABM And Space Defense|year=1999|pages=2–47}}</ref> Though classified at the time, a detailed study on a Soviet space-based laser system began no later than 1976 with the [[Polyus (spacecraft)|Polyus]], a 1 MW [[Carbon dioxide laser]]-based orbital weapons platform prototype. Development was also started on the anti-satellite ''Kaskad'' in-orbit missile platform.<ref>{{cite web|url=http://www.thespacereview.com/article/2394/2|title=The Space Review: Plagiarism in several space history articles (page 2)|date=October 8, 2017|archive-url=https://web.archive.org/web/20171008102950/http://www.thespacereview.com/article/2394/2|archive-date=October 8, 2017}}</ref><ref name="web.archive.org">{{cite web|url=http://arstechnica.com/science/2013/05/the-soviet-response-to-star-wars-that-never-was/2/|title=The secret laser-toting Soviet satellite that almost was – Ars Technica|date=September 26, 2013|archive-url=https://web.archive.org/web/20130926143351/http://arstechnica.com/science/2013/05/the-soviet-response-to-star-wars-that-never-was/2/|archive-date=September 26, 2013}}</ref>

A [[revolver cannon]] ([[Rikhter R-23]]) was mounted on the 1974 Soviet [[Salyut 3]] space station, a satellite that successfully test-fired its cannon in orbit.<ref name=Olberg>{{cite web| url = http://space.au.af.mil/books/oberg/ch02.pdf| title = James Olberg, ''Space Power Theory'', Ch. 2| access-date = June 17, 2013| archive-date = July 12, 2018| archive-url = https://web.archive.org/web/20180712205157/http://space.au.af.mil/books/oberg/ch02.pdf| url-status = dead}}</ref><ref>{{cite web|url=http://www.popularmechanics.com/military/weapons/a18187/here-is-the-soviet-unions-secret-space-cannon/|title=Here Is the Soviet Union's Secret Space Cannon|date=November 16, 2015}}</ref>

In 1979, Teller contributed to a [[Hoover Institution]] publication where he claimed that the US would be facing an emboldened USSR due to their work on [[civil defense]]. Two years later at a conference in Italy, he made the same claims about their ambitions, now emboldened by new space-based weapons. According to popular opinion, shared by author [[Frances FitzGerald (journalist)|Frances FitzGerald]], no evidence validated that such research was carried out. Instead, Teller was promoting his latest weapon, the [[X-ray laser]] that was finding only limited funding, his speech in Italy was a new attempt to synthsize a [[missile gap]].<ref>{{Cite book |last=FitzGerald |first=Frances |url={{google books|plainurl=yes|id=nv2v0fCAONwC|page=128}} |title=Way Out There In the Blue: Reagan, Star Wars and the End of the Cold War |date=2001-02-21 |publisher=Simon and Schuster |isbn=978-0-7432-0377-7 |pages=128 |language=en}}</ref>

In 1979, Reagan visited the [[NORAD]] command base, [[Cheyenne Mountain Complex]], where he was introduced to the extensive tracking and detection systems extending throughout the world and into space; however, he was struck by their comments that while they could track the attack down to the individual targets, they could not stop it. Reagan felt that in the event of an attack, this would place the president in a terrible position, having to choose between immediate counterattack or absorbing the attack while maintaining offensive dominance. Shultz suggested that this feeling of helplessness, coupled with Teller's defensive ideas combined to motivate SDI.<ref name=gps/>{{rp|261–62}}

In the fall of 1979, at Reagan's request, Lieutenant General [[Daniel O. Graham]], the former head of the [[Defense Intelligence Agency|DIA]], briefed Reagan on an updated BAMBI he called High Frontier, a missile shield composed of multi-layered ground- and space-based weapons that could track, intercept, and destroy ballistic missiles, theoretically enabled by emerging technologies. It was designed to replace the [[mutual assured destruction|MAD]] doctrine.<ref>{{cite book|first=Daniel O. |last=Graham|authorlink=Daniel O. Graham |url=http://www.danielgraham.net/content/Chapter14.htm |title=Confessions of a Cold Warrior: An Autobiography|archive-url=https://web.archive.org/web/20070311033905/http://www.danielgraham.net/content/Chapter14.htm |archive-date=March 11, 2007 |publisher= Preview Press|year=1995|isbn=0-9644495-2-8}}</ref> In September 1981, Graham formed a small, Virginia-based [[think tank]] called High Frontier to continue research on the missile shield. [[The Heritage Foundation]] provided High Frontier with research space, and Graham published a 1982 report entitled, "High Frontier: A New National Strategy" that examined in greater detail how the system would function.<ref>{{Cite book |url=http://dx.doi.org/10.1093/acref/9780199759255.001.0001 |title=The Oxford Encyclopedia of American Military and Diplomatic History |date=2013-01-01 |publisher=Oxford University Press |isbn=978-0-19-975925-5 |editor-last=Lynch |editor-first=Timothy J. |volume=2 |pages=360 |chapter=Think Tanks and US Military and Diplomatic Affairs|doi=10.1093/acref/9780199759255.001.0001 }}</ref>

Since the late 1970s, another group had been pushing for the development of a high-powered orbital chemical laser  attack ICBMs, the Space Based Laser (SBL). New developments under [[Project Excalibur]] by Teller's "O-Group" at [[Lawrence Livermore National Laboratory]](LLNL) suggested that a single [[X-ray laser]] could shoot down dozens of missiles with a single shot.<ref>{{cite news | title = 'Cold Fusion' Patents Sought | first = Broad | last = William J. | date = April 13, 1989 |work=The New York Times | url = https://www.nytimes.com/1989/04/13/us/cold-fusion-patents-sought.html }}</ref> The groups began to meet in order to prepare their plans for the incoming president.

The group met with Reagan several times during 1981 and 1982, apparently with little effect, while the buildup of new offensive weaponry like the [[B-1 Lancer]] and [[MX missile]] continued. However, in early 1983, the [[Joint Chiefs of Staff]] met with the president and outlined the reasons why they might consider shifting some of the funding from the offensive side to new defensive systems.

According to a 1983 US Interagency Intelligence Assessment, good evidence indicated that in the late 1960s the Soviets were devoting serious thought to both explosive and non-explosive nuclear power sources for lasers.<ref>{{cite web|url=https://fas.org/spp/starwars/offdocs/m8310017.htm|title=Possible Soviet Responses to the US Strategic Defense Initiative Interagency Intelligence Assessment.1983. "There is good evidence that in the late 1960s the Soviets were giving serious thought to both explosive and nonexplosive nuclear power sources for lasers of an unknown type."|access-date=April 4, 2015|archive-date=May 7, 2015|archive-url=https://web.archive.org/web/20150507003220/http://fas.org/spp/starwars/offdocs/m8310017.htm|url-status=dead}}</ref>