Reflecting some important shifts in US public opinion over the past decade, the poll by Pew Research Centre found that the public's views are more evenly divided today in response to the question, "Why do they hate us?"



Today 43 percent agree with the proposition that the attacks may have been motivated by something "the US did wrong in its dealings with other countries", and 45 percentdisagree. Immediately after the attacks, a majority of respondents (55 percent) rejected that notion, while only a third agreed.



The shift, however, was mainly confined to self-described Democrats and independents, half of whom now believe US policies may have motivated Al Qaeda.



Republicans, on the other hand, remained steadfast, as on a number of other key issues, in their view that the attacks were not motivated by anything the US had done.



The survey also found major differences between age groups on this question. More than half (52 percent) of respondents under 30 said US actions may have motivated the attacks, while only 20 percent of respondents 65 and older were open to that explanation.



A similar shift has taken place over the past decade with respect to the public's belief that it may be necessary to give up civil liberties to curb terrorism, according to the survey.



While 55 percent of respondents agreed with that proposition immediately after 9/11, that percentage has fallen to 40 percent. Conversely, the percentage of those who believe that civil liberties should not be sacrificed rose from 35 percent to a 54-percent majority, the survey found.



The survey, which interviewed more than 1,500 adults Aug 17-21, found that the 9/11 attacks have been seared into the public's collective consciousness in a way that no other modern event ever has.



Six of 10 respondents said they believed 9/11 changed life in the United States in a major way, while only one in 10 said they believe life here remains basically the same as it was a decade ago.