The sources and evidence are copious.
This book is a good place to start...
"Study of Revenge" is, first of all, the story of the Trade Center bombing. Mylroie contends that the mastermind behind the bombing was an Iraqi intelligence agent, Ramzi Yousef, who escaped and left behind the Muslim fundamentalists who participated in the plot and were meant to be caught. She argues that the Clinton administration's mishandling of the event led to the emergence of a fraudulent and dangerous theory about Middle East terrorism–that it is no longer primarily state-sponsored but is carried out by individuals or "loose networks." The misunderstanding is particularly dangerous in light of the prospects for biological terrorism.
In addition to her account of events around the bombing, Mylroie describes how Saddam Hussein has steadily regained strength and eroded the system of postwar constraints that were supposed to hold him in check. She suggests that because of the proscribed unconventional-weapons capabilities Saddam retained in violation of the Gulf War cease-fire–and without the check of U.N. weapons inspectors–he is far more dangerous than is generally recognized.
Mylroie bases her case on a meticulous analysis of the government's evidence in the terrorism trials that followed the Trade Center bombing. Her book is written as a detective story, and the reader is invited to conduct the investigation into state sponsorship of the terrorism that the U.S. government failed to conduct.
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