McDonnell Douglas History Thor IRBM (Douglas 1957)
Thor IRBM (Douglas 1957) D4E-535474

Thor, an intermediate-range ballistic missile, provided nuclear deterrence before ICBMs were ready to assume the role. Thor missiles were later reconfigured as launch vehicles for the Air Force and NASA, providing first the hardware, then the technology for current Air Force and NASA launch systems, including Delta and Delta II launch vehicles.