One thing I've been wondering about ever since 9/11 is whether the date was randomly chosen, or if it was chosen specifically for its resemblance to the American emergency hotline 9-1-1 (or something else)?

It seems like a fairly bizarre coincidence for such a devastating attack to take place on the one day of the year whose date roughly translates to "disaster," but then it also seems rather odd (and kind of comic-book-villain-y, frankly) to time an attack in such a themed way. Also, the rest of the world (as I understand it) would write the date 11-9-2001, which would seem to argue against the connection, except that it was targeted against one of the only nations who would write it 9-11-2001.

Have any Al-Qaida prisoners or documents revealed whether there was any thought put into the timing of the 9/11 attacks? Was the 9-1-1 connection purely coincidental? Were the attacks timed to coincide with something else, like an anniversary of something or a date with special meaning to Al-Qaida or bin Laden? Was there something about early September that made the attacks easier to pull off? Or was the date just chosen at random, without any larger significance at all?

I haven't seen any interviews, exposés, documents or anything else that would point one way or the other. Has anyone seen any definitive word on this?

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    Shortly after the event, I read a claim that Osama Bin Laden choose the date deliberately to taint the North American emergency number 911; but I know of no first-hand evidence to substantiate this claim. Oct 21, 2014 at 22:16
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  • Yeah, this question is pretty well covered by the skeptics.se Q&A. Unfortunately the close:duplicate feature doesn't work across stack exchanges. Oct 21, 2014 at 23:15
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    That Skeptics answer does seem to indicate that the 9-1-1 connection isn't valid. However, the other part of my question remains: was that date significant in any other, perhaps more practical way? Like D-Day taking weather into account or the Columbine shootings coinciding with several other attacks, was Sept 11th a purely random date, or did it have any practical or symbolic significance?
    – Nerrolken
    Oct 21, 2014 at 23:20
  • One of my friends posted something on Facebook that it was the anniversary of some event in Islamic history, but I can't remember what it was (and this was years ago now). No clue if he was actually right. Note that this would most likely be in (one of) the Islamic calendars, which varies wildly from the Gregorian/ISO calendar the world at-large uses. You'd first have to figure out what the day was in those calendars, then look for anniversaries based on that... Oct 23, 2014 at 14:14

4 Answers 4


There was no announcement by the terrorists after 9/11 using that name nor taking ownership for the events (check me on that). The name "9/11", and the significance of the date, was given by the US media after the fact, something the terrorists could not have likely predicted. It doesn't follow the pattern of any of the previous big attacks on the US. We don't refer to the USS Cole bombing as 10/12, Pearl Harbor as 12/7, nor Oklahoma City as 4/19. Following that pattern, 9/11 should have been referred to as "Twin Towers" or "WTC" or something after the location, not the date.

If 9/11 was chosen to have special meaning, it wasn't likely to be related to 911. As pointed out on Skeptics, the rest of the world writes the date as 11/9. Furthermore, in the Islamic Calendar, Sept 11, 2001 was Tuesday 23 Jumaada al-THaany 1422 A.H. or 6/23 (or 23/6).

Martin Gardner uses the example of finding "fiveness" in the Washington Monument to show you can find significance in any numbers (Numerology) if you look hard enough. Here's a list of what's special about the first 10,000 numbers (mostly mathematical). Similarly, you can find something interesting about every day of the calendar year. Throw in Bible and Qur'an references for good measure, feel free to pick from any book/chapter. Use 9:11 or 11:9 or 911 or 119 or 9.11 or 11.9.

In order to coordinate the attacks they had to pick a date. That was likely an operational consideration. Given how difficult it was to coordinate the attacks, and they wanted it to be even bigger, adding in the extra complication of an arbitrary deadline seems an amateurish complication. Then again, I've worked on some business projects which did just that.


Don't know if Al Qaeda was conscious of it or not, but 11 September 1683 was the all-time high water mark of the advance of Muslim armies into Christendom, when the Ottoman Turks stood outside the walls of Vienna. They were defeated and driven back the following day, 12 September 1683.

I also don't know if it is significant that 12 September is of course a date in the Western, Christian calendar. Muslims do use it for convenience for secular purposes. However, they have their own lunar month based calendar used to determine date of Ramadan etc., in which year 1 is the year Mohammed moved to Medina (where he established the first Muslim government).

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    I have read a bit of bin-Laden's and other al-Qaeda leaders' writings, and one thing they definitely are is students of history. This was the day the Muslims began their invasion of Europe, I have no doubt they were aware of this fact. Why pick a random day for the attack and cause possible confusion, when you can pick a day everyone is going to know already. This answer needs more upvotes, but you need to expound on what you are talking about (the Battle of Vienna, no?). Jan 8, 2023 at 12:17
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    The Ottoman siege of Vienna began July 14th. As for Sept 11th, it seems odd that they would memorialize the day before the battle nor why they'd memorialize a disastrous failure of the Ottomans.
    – Schwern
    Jan 9, 2023 at 20:19

Without suggesting there is any documented evidence of a connection, 9/11 was also the date of another recent aerial attack on the downtown of a major Western city, Pinochet's 1973 coup in Santiago, Chile.

  • Actually there were panic movements in Chile on September 11, 2001 and the Chilean stock exchange collapsed because people thought that the attack on WTC was done by some Chilean extremists for revenge (the USA is widely seen as having supported Pinochet's coup) and they were fearing retalation...
    – Evargalo
    Oct 13, 2020 at 8:21
  • You forgot many import events happening on 9 september: onthisday.com/events/september/9
    – Jos
    Jan 8, 2023 at 0:31

Mountain Meadows Massacre

While I have not been able to find evidence that the planners of the 2001 hijackings were specifically aware of it or considered it important, the date of September 11 was already significant in the United States as a date associated with religiously-colored violence.

On September 11, 1857, a militia composed of followers of the Church of Jesus Christ of Latter-day Saints ("LDS" or "Mormons") attacked and slaughtered most of the members of a non-Mormon wagon train headed west to California via Utah. LDS member John D. Lee was convicted and executed for leading the attack.

Here is an article from the LDS church in which they admit that the attack was planned and executed by local church leaders but that an order from Brigham Young (then the president of the church) not to go forward with the attack did not reach the militia in time.

  • I wouldn't call MMM significant in the US, maybe in Utah it is and New York is a long way from Utah. I'd wager overwhelmingly most Americans don't know about it. I think we can skip listing events which happened on Sept 11th, and restrict answers to those where we can show a definitive connection.
    – Schwern
    Jan 9, 2023 at 20:16

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