It led to the rise of the head-chopping and liver-eating Daesh (AKA Islamic State) and 15 years later we are still there in Iraq and also in Syria, but the war has a different name.
It led to the shameful legalization, albeit temporarily, of torture. Destroying the reputation of my country in the minds of much of the rest of the world. Changing the name of Uncle Sugar to Uncle Sadism or Uncle Swine perhaps.
$2 trillion in initial costs! That will rise to $6-trillion due to healthcare costs and compound interest according to Brown University studies. Those figures do not include the current costs of the ongoing war against Daesh. My latest great-grandbaby will be still paying off that debt when she is my age.
The gallons of blood on all sides, military and civilian, that have been and are still being shed there is uncountable and a bit hard to conceive in the 21st century.
And yet:
Rumsfeld received the <i>'Defender of the Constitution Award'</i> after he retired:
Cheney was recently honored with a bust in the US Capitol building:
Junior Bush received the <i>'Thayer Award'</i> from West Point last October:
https://www.army.mil/article/195682/george_w_bush_receives_west_points_thayer_award
UPDATE:
As pointed out to me, the invasion of Iraq also:
helped al-Qaeda to become stronger
helped Iran to become more influential
helped China to become a superpower
helped Vladimir Putin look like a Statesman