The hardest thing for most people to accept is that the government would lie to and attack its own people. Bzzzzzttt, wrong!
http://en.wikipedia.org/wiki/Operation_Northwoods
All it would've taken was a couple more people to go along with it and you have implementation. On 9/11, the scale was simply escalated. There's a precident for this...Nero burning Rome, Hitler burning the Reichstag, etc.
But these warmongers in the JCoS didn't stop there...
Operation Northwoods called for a war in which many patriotic Americans and innocent Cubans would die senseless deaths, all to satisfy the egos of twisted generals back in Washington, safe in their taxpayer financed homes and limousines.
One idea seriously considered involved the launch of John Glenn, the first American to orbit the earth. On February 20,1962, Glenn was to lift off from Cape Canaveral, Florida, on his historic journey. The flight was to carry the banner of America's virtues of truth, freedom, and democracy into orbit high over the planet. But Lemnitzer and his Chiefs had a different idea. They proposed to Lansdale that, should the rocket explode and kill Glenn, "the objective is to provide irrevocable proof that . . . the fault lies with the Communists et al Cuba [sic.]"
This would be accomplished, Lemnitzer continued, "by manufacturing various pieces of evidence which would prove electronic interference on the part of the Cubans." Thus, as NASA prepared to send the first American into space, the Joint Chiefs of Staff were preparing to use John Glenn's possible death as a pretext to launch a war.
Glenn lifted into history without mishap, leaving Lemnitzer and the Chiefs to begin devising new plots which they suggested be carried out "within the time frame of the next few months."
Among the actions recommended was "a series of well coordinated incidents to take place in and around" the U.S. Navy base at Guantanamo Bay, Cuba. This included dressing "friendly" Cubans in Cuban military uniforms and then have them "start riots near the main gate of the base. Others would pretend to be saboteurs inside the base. Ammunition would be blown up, fires started, aircraft sabotaged, mortars fired at the base with damage to installations."
The suggested operations grew progressively more outrageous. Another called for an action similar to the infamous incident in February 1898 when an explosion aboard the battleship Maine in Havana harbor killed 266 U.S. sailors. Although the exact cause of the explosion remained undetermined, it sparked the Spanish-American War with Cuba. Incited by the deadly blast, more than one million men volunteered for duty. Lemnitzer and his generals came up with a similar plan. "We could blow up a U.S. ship in Guantanamo Bay and blame Cuba," they proposed; "casualty lists in U.S. newspapers would cause a helpful wave of national indignation."
There seemed no limit to their fanaticism: "We could develop a Communist Cuban terror campaign in the Miami area, in other Florida cities and even in Washington," they wrote. "The terror campaign could be pointed at Cuban refugees seeking haven in the United States.
You think a few thousand people and billions in damage would deter people intent on gaining power (Patriot Act...what a sickening name) and expanding the military industrial complex via global actions?