Most conspiracy theories about the 9/11 terrorist attacks have been debunked by
this book, so i have removed my own (obsolete) texts.
No matter how much scientists write about this, there will always be fanatics
who still believe what they want to believe. I feel this is a lost cause.
Believing in conspiracy theories is a bit like being members of a religion,
and proving that the conspiracy theory is wrong is like trying to prove that
gods do not exist.
(This very book is a good example of the religious fanaticism of the conspiracy theorists: many of them criticized the book's chapters even before it was published, and before they read it).
Why the World Trade Center collapsed:
The fire wasn't hot enough to melt the steel: as far as i know, there has never been a claim that the steel melted completely in the fire, but there is no doubt that an intense prolonged fire causes a reduction in the strength of the steel. According to "Fire Protection Handbook 17th Edition" (National Fire Protection Association, 1992, pages 6-62 to 6-70): "Structural steel begins to soften around 425 degrees centigrades and loses about half of its strength at 650 degrees.
These conspiracy theories are paradoxical mainly because it would take thousands and thousands of people to cooperate in plotting them and executing them. The cover up should involve half of Washington. The very passengers who, according to some conspiracy theories, never died, should be kept alive somewhere. Their relatives should be part of the conspiracy. That phone calls were made by the passengers is hard to doubt, as their voices were recognized by their relatives and friends. If they were not made from planes, then those passengers (none of which worked for the CIA) must have accepted to make them from somewhere else. Etc etc.
Last but not least, the "Joint Inquiry into Intelligence Community Activities before and after the Terrorist Attacks of September 11, 2001" "Final Report of the National Commission on Terrorist Attacks Upon the United States" was signed by sworn enemies of the Bush administration who would love to find the slightest proof of misconduct.
It takes an amazing amount of fanaticism to believe these conspiracy theories.