You have a few misconceptions about the build-up to the 9/11 attacks under the lawless Bush/Cheney administration, but perhaps your point about hatred being invalid (or at least not constructive) when targeting only President Bush but not his diabolically evil nation-destroying handlers (Cheney, Rumsfeld, Wolfowicz, the Council on National Policy, Heritage Foundation, Karl Rove, or the D.C.-based religious-fanatic CULT The Family/YWAM which controls every move the GOP makes) is unfair.
The unconstitutional 2000 election cheat by the GOP that illegitimately placed the incompetent GW Bush into power even though Al Gore won Florida (where GW's brother Jeb Bush rigged the results) sparked nation-wide outrage. We, the American people, were ROBBED of our votes' results and this still rankles most of us, as it should for those among us who value the U.S. Constitution.
Cheney (a.k.a., "Darth Vader") chose himself as VP due to his ties with the shadow-government CIA connections set up during the alzheimered Reagan/Bush days, his long-time ties with the war-profiteering Carlyle Group, and his allegiance to the abovementioned fundamentalist-extremist CULT The Family (a.k.a., Youth With A Mission, The Federation, Heritage Foundation) that has as its goal a THEOCRATIC COUP (one-religion-only takeover of the U.S. government from within the political system), and Cheney then brought in the same evil puppeteers Reagan had: Rumsfeld, Rove, and Wolfowicz.
As a person, GW Bush was weak and easily manipulated by his puppeteers, a long-time alcoholic and cocaine addict whose powerful daddy or his questionable connections tended to bail him out whenever he ran a business into the ground or screwed up in life. One of the best things GW ever did was to marry Laura Bush, who made a gracious First Lady.
As to 9/11: Read then-counter-terrorism specialist and NSA Director Richard Clarke's book, "Against All Enemies" to learn that GW ignored repeated written and oral warnings that, had they been heeded, would have prevented the 9/11 attacks. GW's brother Marvin Bush, as well as his own maternal uncle and cousin, Wirt Walker I and Wirt Walker III, were in charge (on the Board) of Securacom that provided "security" for the World Trade Center, for United Airlines (two 9/11 planes were United), for Dulles International Airport (two 9/11 planes flew out of Dulles), and also for the notorious Riggs Bank that laundered money for two of the 9/11 attackers through the wife of long-time Bush family friend Prince Bandar (see Michael Moore's documentary, "Fahrenheit 9/11"), who was a trained Saudi Arabia army pilot and long-time friend of the bin Ladens.
Consider this too, as terrible as it may seem: According to then-Treasury Secretary Paul O'Neill, GW Bush and Dick Cheney were huddled together only four days after being sworn in on January 20, 2001 looking for "an excuse the public would buy" to illegally invade Iraq. There is a very strong possibility that GW was encouraged to let the warned-about attacks occur as an evil "means to an end" and that any deaths resulting from allowing the attack to happen would be considered "collateral damage" in order to gain a foothold on the oil-right fields of the Middle East.
Always-fail economic policies also factor in to the loathing felt for the GOP/Bush/Cheney years.