A recent poll conducted across the United States has underlined peoples' fear of another terrorist attack in the country.
Several thousand people expressed fear about terrorism surfacing anywhere, like in public transport system.
Five years after the attacks, terrorist threat is still evolving because of the fear that none of the accused have been punished or jailed so far.
The terrorists' unsuccessful attempt to blow up the US-bound trans-Atlantic flights mid-air early last month, which was foiled by the British security agencies, came as a stark reminder of 9/11.
Al Qaeda leader Osama bin Laden, who claims to have planned the attacks on the World Trade Center twin towers on September 11, is still scot free. The only person convicted was a Frenchman, Zacarias Moussaoui, who was jailed when the incident took place.
Such details have only compounded the situation, particularly in New York. Among the poll's findings, 59 per cent nationally approved of President George W Bush's response to the 9/11 terrorist attacks while less than half in New York and Washington felt that way, the survey adds.
Nationwide, 35 per cent were worried that they could be victims of terrorism, a number that rose to 43 per cent after the alleged terrorist plot in Britain came to light.
The findings are based on a national poll conduted between August 7-9 and August 15-17.
Asked whether the attacks changed their lives, half the people surveyed, said it has.
They said they were more cautious of their surroundings now.
Some were more afraid of flying and others said they understood the importance of family, the survey adds.