Mr. Obama this month presented his government’s findings on how the plot went undetected. But a detailed review of the episode by The New York Times, including more than two dozen interviews with White House and American intelligence officials and with counterterrorism officials in Europe and Yemen, shows that there were far more warning signs than the administration has acknowledged.
The officials also cited lapses and misjudgments that were not disclosed in the declassified government report released Jan. 7 about what went wrong inside the nation’s counterterrorism network.
In September, for example, a United Nations expert on Al Qaeda warned policy makers in Washington that the type of explosive device used by a Yemeni militant in an assassination attempt in Saudi Arabia could be carried aboard an airliner….