A more "mature" and less corrupt administration would have paid heed to the multiple written and oral warnings instead of deliberately allowing the 9/11 attacks to occur as a Cheney-Bush-desired "excuse the American people would buy" for illegally invading Iraq---something they had been plotting only four days after taking office in January 2001 (Ron Suskind, "The Price of Loyalty").
The politicization of 9/11 in its immediate aftermath by the very people who had allowed the catastrophe to occur was truly sickening, especially once I discovered that GW's own brother Marvin Bush, his maternal uncle Wirt Walker I, and his maternal cousin Wirt Walker III were in charge of Securacom (changed to Securatec, Inc. post 9/11), the company the Bush/Cheney administration contracted to provide "security" for the World Trade Center, for United Airlines (two 9/11 planes were United), and for Dulles International Airport from whence two attack planes flew. This same three were on the Board for Riggs Bank (Wirt I chairman) that was discovered to have laundered money for two of the hijackers through the wife of Prince Bandar, a long-time GW Bush friend (see Michael Moore's documentary ""Fahrenheit 9/11") and also a trained Saudi army pilot and friend to the bin Laden family. This is not saying that the lawless Bush/Cheney administration was in on the actual planning---they just saw any attack would be that "excuse the public would buy" and decided to let whatever attack pending happen as a means to their desired end, with Cheney, Rumsfeld, and Wolfowicz preying upon GW's evangelically-extremist bent to convince him to go along.
A more mature and less evil administration would have averted the attacks on 9/11---and hundreds of thousands of lives would have been saved. No war in Afghanistan, no ILLEGAL invasion of a sleeping Iraq (a nation that never once attacked the U.S.), no destruction of the WTC in New York and therefore no lives lost...no phony cowboy "bring it on" insanity...aah, to dream.