Second Smoking Gun
March '00 - Filming begins for The Lone Gunmen's 'Pilot' episode that depicts a US plot to crash an electronically hijacked Boeing 727 into WTC and blame foreign terrorists to provoke war and increase military's budget (KC Star), March '01 - 'Pilot' episode airs on FOX TV, 6 months before attacks (TV Guide), Lone Gunmen co-producer hopes WTC attack wasn't 'somehow inspired' by anything they did. (KC Star)
Given that intelligence shows that the 9/11 attacks took years to execute, it is highly unlikely that even the US government could coordinate something like this in just one year. It's plausible, but highly unlikely.
There is no documentation that any of the writers or the producers had any government information before putting together the pilot episode. I find this to be purely coincedental.