He received his undergraduate degree in physics and his PhD in nuclear engineering from MIT. Postol worked at Argonne National Laboratory, where he studied the microscopic dynamics and structure of liquids and disordered solids using neutron, X-ray and light scattering techniques, along with molecular dynamics simulations. He also worked at the Congressional Office of Technology Assessment, where he studied methods of basing the MX missile, and later worked as a scientific adviser to the Chief of Naval Operations.
After leaving the Pentagon, Postol helped build a program at Stanford University to train mid-career scientists to study weapons technology in relation to defense and arms control policy. In 1990, Postol received the Leo Szilard Prize from the American Physical Society for "incisive technical analysis of national security issues that [have] been vital for informing the public policy debate."; in 1995, he received the Hilliard Roderick Prize from the American Association for the Advancement of Science and in 2001, he received the Norbert Wiener Award from Computer Professionals for Social Responsibility for "uncovering numerous and important false claims about missile defenses.". On September 28, 2016 the Federation of American Scientists awarded Professor Theodore Postol from MIT their annual Richard L. Garwin Award, "that recognizes an individual who, through exceptional achievement in science and technology, has made an outstanding contribution toward the benefit of mankind."
The Patriot Missile was used in Operation Desert Storm to intercept descent-phase SCUD missiles fired by Iraq. The U.S. Army claimed a success rate of 80% in Saudi Arabia and 50% in Israel, claims that were later reduced to 70% and 40%. But President George H. W. Bush claimed a success rate of more than 97 percent during a speech at Raytheon's Patriot manufacturing plant in Andover, Massachusetts during the Gulf War, declaring, the "Patriot is 41 for 42: 42 Scuds engaged, 41 intercepted!" In April 1992, Postol told a House committee that "the Patriot's intercept rate during the Gulf War was very low. The evidence from these preliminary studies indicates that Patriot's intercept rate could be much lower than 10 percent, possibly even zero." Postol later went on to criticize the Army's "independent" Analysis of Video Tapes to Assess Patriot Effectiveness as being "seriously compromised" by the "selective" and "arbitrary" use of data. A House Government Operations Committee investigation in 1992 concluded that, contrary to military claims on effectiveness, Patriot missiles destroyed only 9 percent of SCUD missiles during attempts at interception.
In 1996, Nira Schwartz, a senior engineer at defense contractor TRW blew the whistle against TRW for exaggerating the capabilities of an antiballistic missile sensor. The sensor was subsequently used in a "successful" missile test in 1997. The then-Ballistic Missile Defense Organization launched an investigation in 1998 and asked a Pentagon advisory board called POET (Phase One Engineering Team), which included two staff members from MIT's Lincoln Laboratory, to review performance of TRW software, using data from the 1997 flight test. These engineers concluded in their report that Schwartz's allegations were untrue and despite failure of the sensor, the software "basically worked the way TRW said it worked." In December 1998, TRW's contract was not extended by the government, which chose a competing system built by Raytheon.
In 2000, Schwartz gave Postol an unclassified version of the POET report from which sensitive text and graphs had been removed. Based on this redacted report, he notified the White House and senior MIT officials of possible fraud and research misconduct at TRW and MIT Lincoln Laboratory. The Pentagon responded by classifying the letter and dispatching Defense Security Service members to his office. Three agents of the Defense Security Services arrived unannounced to his campus office and attempted to show him other classified documents, but Postol refused to look at them. If he had read them, he would not have been able to criticize the antimissile system without putting his security clearance at risk. Postol claimed the visit was meant to silence him, which was denied by the Defense Security Services.
Postol demanded the MIT administration under President Charles Vest and Provost Robert Brown investigate possible violations to MIT policies on research misconduct. The administration initially resisted, but later appointed another faculty member to conduct a preliminary investigation. In 2002, this professor's investigation found no evidence of a credible error, but he subsequently recommended a full investigation when Postol provided a statement of additional concerns. A subsequent 18-month investigation by the General Accounting Office in 2002 found widespread technical failures in the anti-missile system, contradicting the original report in 1997. In May 2006, a panel composed of MIT faculty members concluded that the investigator recommended a full investigation "because of his inability to exhaust all the questions that arose during the inquiry," not because it appeared likely misconduct had occurred, and that a full investigation had not been warranted.
Under National Science Foundation regulations governing research misconduct, a preliminary inquiry should be completed within 90 days of an allegation, and a full investigation within 180 days subject to penalties as severe as suspension of federal funding. By December 2004, four years later, no formal investigation had been performed, and the Missile Defense Agency formally rejected MIT's request to investigate the classified data. Postol asserts that the MIT administration has been compliant with the Pentagon's attempts to cover up a fiasco by dragging its feet on an investigation because defense contracts through Lincoln Laboratory constitute a major portion of MIT's operating budget.
In early 2006, a compromise was reached whereby MIT would halt any attempt to conduct its own investigation and senior Air Force administrator Brendan B. Godfrey and former Lockheed Martin chief executive Norman R. Augustine would lead a final investigation. Postol disputes the impartiality of this new investigation as Augustine was CEO while Lockheed was a contractor with NBMD.
In May 2006, an MIT Ad-Hoc Committee on Research Misconduct Allegation concluded delays in the investigation were caused by a number of factors, including: "initial uncertainty about the applicability of MIT's research misconduct policy to a government [non-MIT] report"; government classification of relevant information, possibly in an attempt to make it unavailable to plaintiffs in the TRW whistle-blower trial; and Postol's failure to provide a clearly written summary of his allegations, which changed repeatedly during the investigation. The committee also found that Postol repeatedly violated MIT confidentiality rules "causing personal distress to the Lincoln Laboratory researchers, their families and colleagues".
In September 2009, President Barack Obama announced that his administration was scrapping the Bush administration's proposed anti-ballistic missile shield in Europe and replacing it with reconfigured SM-3 missiles. A "Ballistic Missile Defense Review" was completed in March 2010 concluding that existing ballistic missile defense technologies provided a reliable and robust defense against limited ICBM attacks. In May 2010, Postol and George N. Lewis published an analysis concluding that the majority of SM-3 interceptor tests classified as "successful" actually failed to destroy incoming warheads. The Missile Defense Agency challenged the New York Times article, claiming that the SM-3 program is one of the most successful programs within the Department of Defense and that the New York Times chose not to publish information supplied by the MDA in response to the allegations made by Postol and Lewis.
In July 2014, Postol was quoted in the MIT Technology Review criticising the effectiveness of the Israeli Iron Dome antimissile system. The article received so many negative comments that the website invited Postol to present his evidence. His response, in August, was based on photographic evidence of the system in operation (although no sources are given in the article for the photographs).
With Richard Lloyd, an expert in warhead design at the military contractor Tesla Laboratories, Postol has written about the 2013 Ghouta chemical attack. Analysing YouTube footage of the attacks and its aftermath, they believed they found a number of items to be inconsistent with the US government's claims about the incident. Postol subsequently worked with Maram Susli (known online as "Syria girl" or "Partisan girl") to develop their analysis of the Ghouta attack.
Postol has also criticized the unclassified intelligence assessment released by the Trump White House blaming the air forces of Syrian President Bashar al-Assad for the April 2017 Khan Shaykhun chemical attack.
Based on his own analysis of the photographic evidence, Postol initially argued that the chemical attack was not an air raid, but conducted from the ground using a multiple rocket launcher, most probably a 122mm artillery rocket tube filled with a chemical agent and detonated by an explosive charge laid on top of it. On 18 April, Postol published a claim analysis of photo evidence of the smoke plume conclusively showed that a crater he identified as the site of rebel-caused ground explosion was the site of sarin release.On 21 April, he revised this view: "In my earlier report released on April 18, 2017 I misinterpreted the wind-direction convention which resulted in my estimates of plume directions being exactly 180° off in direction." Later in April, Postol claimed that the "French Intelligence Report of April 26, 2017 directly contradicts the White House Intelligence Report of 11 April, 2017". The following day he revised his view, noting that he had confused the date and location for a different chemical attack four years earlier.
Postol argued that none of the forensic evidence in the New York Times video and a follow-on Times news article on the alleged nerve agent attack in Khan Sheikhoun on April 4, 2017 supports the conclusions reported by the New York Times.
In August 2017, Postol shared with Newsweek a paper he co-authored with Markus Schiller and Robert Schmucker of Schmucker Technologies claiming that missiles tested earlier in 2017 by the DPRK that had been widely described as intercontinental ballistic missiles were in reality incapable of delivering a nuclear warhead to the mainland United States.Blair, Bruce G.; Dean, Jonathan; Fetter, Steve; Goodby, James; Lewis, George N.; Postol, Theodore; Von Hippel, Frank N.; Feiveson, Harold A. (June 1999). The Nuclear Turning Point: A Blueprint for Deep Cuts and De-Alerting of Nuclear Weapons. Brookings Institution Press. ISBN 978-0-8157-0953-4.