The government would never lie to further their own secret agenda would they???
Initially, the U.S. Navy's own historians now say that the sinking of the USS Maine -- the justification for America's entry into the Spanish-American War -- was probably caused by an internal explosion of coal, rather than an attack by the Spanish.
It is also now well-accepted that the Gulf of Tonkin Incident which led to the Vietnam war was a fiction.
And America knew of the Japanese plan to attack Pearl Harbor -- down to the exact date of the attack. See this BBC special and this short essay. Indeed, it has recently been discovered that the FDR administration took numerous affirmative steps to ensure that the Japanese attack would be successful, such as giving commanders in Hawaii false information about where Japanese war ships were located.
Indeed, two lies were also used to justify the 1991 Gulf War: the statement that Iraqis murdered Kuwaiti babies and the statement that Iraqi troops were massed on the border with Saudi Arabia (second half of video)(technically, the statement about Kuwaiti babies did not come from the U.S. government).
And what does this history of deception imply about 9/11?