Editing Strategic Defense Initiative (section)

===Treaty obligations===

[[File:SDIO KEW Lexan projectile.jpg|thumb|SDI was not just lasers; in this Kinetic Energy Weapon test, a {{convert|7|g|oz|order=flip|adj=on}} [[Lexan]] projectile was fired from a [[light-gas gun]] at a velocity of {{convert|23000|ft/s|m/s mph}} at a cast aluminum block.]]

Another criticism of SDI argued that it would be inconsistent with existing treaties. The [[Anti-Ballistic Missile Treaty]] and its subsequent protocol,<ref>{{cite web|url=https://fas.org/nuke/control/abmt/text/abmprot1.htm |title=Protocol to the Treaty between the United States of America and the Union of Soviet Socialist Republics on the Limitation of Anti-Ballistic Missile Systems|date=May 24, 1976}}</ref> which limited missile defenses to one location per country at 100 missiles each ([[ABM-1 Galosh|which the USSR had]] and the US did not){{clarify|date=January 2025|reason=It's unclear what the content in parentheses means, and how the ABM-1 Galosh is specifically relevant to this.}}, would have been violated by SDI ground-based interceptors. The [[Nuclear Non-Proliferation Treaty]] requires that "Each of the Parties to the Treaty undertakes to pursue negotiations in good faith on effective measures relating to cessation of the nuclear arms race at an early date and to nuclear disarmament, and on a treaty on general and complete disarmament under strict and effective international control." Many{{Who|date=October 2009}} viewed deployment of ABM systems as an escalation, and therefore a violation of this clause, although this view was not universal.{{citation needed|date=June 2024}}

The [[Outer Space Treaty]] of 1967 required "States Party to the Treaty undertake not to place in orbit around the Earth any objects carrying nuclear weapons or any other kinds of weapons of mass destruction, install such weapons on celestial bodies, or station such weapons in outer space in any other manner."<ref>{{cite book |title=Nuclear weapons and contemporary international law |last1=Singh |first1=Nagendra |last2=McWhinney |first2=Edward |year=1989 |publisher=Martinus Nijhoff |isbn=90-247-3637-4 |page=236 |url=https://books.google.com/books?id=r2IfMEpPUIsC&pg=PA236}}</ref> This clause forbade the US from pre-positioning in Earth orbit any devices powered by nuclear weapons and any devices capable of "mass destruction". A space-stationed nuclear-pumped X-ray laser would have violated this treaty, since other SDI systems did not require the pre-positioning of nuclear explosives in space.