Overview: After four years of research, the release of official conclusions left many unsatisfied. Both buildings were designed to survive the impact of a commercial airliner and the fireproofed steel structures should have survived the fires that followed - yet within two hours both towers had collapsed. In addition, video footage of molten metal pouring from the damaged floors and eyewitness reports of explosions before the collapse were not addressed fully, fuelling conspiracies of a government plot to destroy the towers and drag America into a war on terror. Retired chemist...