The US authorities has described it arsenic the "most egregious transgression enactment connected American ungraded successful modern history".
A quarter of a century on, the alleged mastermind’s trial has yet to begin, and families of those killed fear that time for justice is running out.
Tom Resta’s brother John and his sister‑in‑law Sylvia, who was seven months pregnant, were among the roughly 3,000 people killed on 11 September 2001 when hijackers flew planes into the World Trade Center in New York City and the Pentagon in Virginia; a fourth plane crashed in a Pennsylvania field after passengers fought back.
The couple had been preparing their unborn child’s nursery, painting it with characters from the children’s TV show *Blue’s Clues* in the days before 9/11. They had dreamed of having a baby and doted on the children of friends and family.
On the morning of the attacks, the pair—both traders—were working on the 92nd floor of the north tower of the World Trade Center.
"After each this time, it inactive chokes maine up," Resta told the BBC done tears. While 25 years person passed, helium said 9/11 was "almost constantly" connected his mind.
Resta has visited the US naval base at Guantanamo Bay four times to observe the pre‑trial hearings of alleged 9/11 mastermind Khalid Sheikh Mohammed and his co‑defendants, a process he calls "laborious and tedious".
A detention facility was established at the base in south‑eastern Cuba during the "war on terror" that followed the 9/11 attacks. Mohammed—often referred to as KSM—has been held there for 20 years without ever being convicted.
Relatives of victims take part in a lottery to attend proceedings in a high‑security courtroom where thick glass separates them and members of the press from the defendants.
The pre‑trial process has been underway for so long that it has been overseen by five different military judges.
Last month, as the 25th anniversary approached, there was a flurry of activity and what appeared to be a breakthrough, with a trial date set for Mohammed in June 2028.
Nevertheless, Resta said he is bracing himself for further delays, and with so much time having elapsed, some of his relatives worry they may not live long enough to see the trial.
"My father will be 98 in November, and I don't think he's expecting to see it. I have a lot of family members