The 20th anniversary of the September 11 attacks: a quick guide

10 September 2021

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Nigel Brew
Foreign Affairs, Defence & Security

This year marks the 20th anniversary of the terrorist attacks of 11 September 2001 when four hijacked planes in the US were crashed into either the ground or buildings, including the World Trade Center in New York, killing almost 3,000 people from more than 80 different countries. This quick guide summarises the initial response to the attacks and some of the comments made by Australian parliamentarians at significant anniversaries over the last two decades, and remembers the ten Australians killed.

Australian flag recovered from the ruins of the World Trade Center, New York, after the attacks of 11 September 2001. It is now held in the National Museum of Australia.

Australian flag recovered from the ruins of the World Trade Center, New York, after the attacks of 11 September 2001. It is now held in the National Museum of Australia.

(Source: National Museum of Australia)

Initial response

The then Australian prime minister, John Howard, who happened to be in Washington at the time, began a press conference on 11 September 2001 by reading a message he had just sent to the US President, George W Bush:

Dear Mr President. The Australian Government and people share the sense of horror experienced by your nation at today's catastrophic events and the appalling loss of life. I feel the tragedy even more keenly being here in Washington at the moment.

In the face of an attack of this magnitude, words are always inadequate in conveying sympathy and support. You can however be assured of Australia's resolute solidarity with the American people at this most tragic time.

My personal thoughts and prayers are very much with those left bereaved by these despicable attacks upon the American people and the American nation.

Describing it as ‘a very tragic day in the history of a great nation’, Mr Howard went on to say:

I can only hope, as I know all decent people around the world will, that those responsible for this despicable series of attacks upon the United States will be hunted down and meted out the justice that they so much deserve.

But the only other thing I can say to you is really on behalf of all the Australians here is to say to our American friends who we love and admire so much, we really feel for you. It is a terrible day … And as I say words aren’t very adequate but they are a sign that we feel for our American friends. We will stand by them, we will help them, we will support actions they take to properly retaliate in relation to these acts of bastardry against their citizens and against what they stand for.

On 12 September the United Nations Security Council adopted Resolution 1368 (2001) condemning the attacks, and members of the North Atlantic Treaty Organization sought to invoke Article 5 of NATO’s foundational North Atlantic Treaty, which provides for the collective self-defence of member states against armed attack:

The Parties agree that an armed attack against one or more of them in Europe or North America shall be considered an attack against them all and consequently they agree that, if such an armed attack occurs, each of them, in exercise of the right of individual or collective self-defence recognised by Article 51 of the Charter of the United Nations, will assist the Party or Parties so attacked by taking forthwith, individually and in concert with the other Parties, such action as it deems necessary, including the use of armed force, to restore and maintain the security of the North Atlantic area.

Any such armed attack and all measures taken as a result thereof shall immediately be reported to the Security Council. Such measures shall be terminated when the Security Council has taken the measures necessary to restore and maintain international peace and security.

Similarly, on 14 September Prime Minister Howard announced that the Australian Government had decided, in consultation with the US, ‘that Article IV of the ANZUS Treaty applies to the terrorist attacks on the United States’, based on the belief that ‘the attacks have been initiated and coordinated from outside the United States’. This was the first—and remains the only—time the ANZUS Treaty had been invoked since its inception in 1952. Article IV of the Security Treaty between Australia, New Zealand and the United States of America (ANZUS Treaty) provides:

Each Party recognizes that an armed attack in the Pacific Area on any of the Parties would be dangerous to its own peace and safety and declares that it would act to meet the common danger in accordance with its constitutional processes.

Any such armed attack and all measures taken as a result thereof shall be immediately reported to the Security Council of the United Nations. Such measures shall be terminated when the Security Council has taken the measures necessary to restore and maintain international peace and security.

This action was included in a parliamentary motion moved by the prime minister and agreed to on 17 September 2001, which stated that the Australian House of Representatives:

(1) expresses its horror at the terrorist attacks which have claimed so many lives in the United States of America;

(2) conveys to the Government and people of the United States of America the deepest sympathy and sense of shared loss felt by the Government and people of Australia;

(3) extends condolences to the families and other loved ones of those Australians killed or missing as a result of the attacks;

(4) declares that such attacks represent an assault, not only on the people and the values of the United States of America, but of free societies everywhere;

(5) praises the courageous efforts of those engaged in the dangerous rescue operation still underway;

(6) believes that the terrorist actions in New York City and Washington DC constitute an attack upon the United States of America within the meaning of Articles IV and V of the ANZUS Treaty;

(7) fully endorses the commitment of the Australian Government to support within Australia's capabilities United States-led action against those responsible for these tragic attacks; and

(8) encourages all Australians in the wake of these appalling events to display those very qualities of tolerance and inclusion which the terrorists themselves have assaulted with such awful consequences.

Another 59 members spoke to the motion, which was agreed to with members indicating their support by rising and standing for a minute’s silence. Select comments made in support of the motion follow:

It goes beyond the death so cruelly inflicted without warning, without justification and without any skerrick of moral authority on innocent people merely going about their daily lives; its context represents a massive assault on the values not only of the United States of America but also of this country—the values of free men and women and of decent people and decent societies around the world. It is an act of terror. It is an act which is repugnant to all of the things that we as a society believe in.

As we struggle as Australians and as we struggle as citizens of the world to come to terms with what has happened, it is certain, as others have said, that the world has changed. We are all diminished, we are all changed, and we are all rather struggling with the concept that it will never be quite the same again. 

In every way, the attack on New York and Washington and the circumstances surrounding it did constitute an attack upon the metropolitan territory of the United States of America within the provisions of articles IV and V of the ANZUS Treaty. If that treaty means anything, if our debt as a nation to the people of the United States in the darkest days of World War II means anything, if the comradeship, the friendship and the common bonds of democracy and a belief in liberty, fraternity and justice mean anything, it means that the ANZUS Treaty applies and that the ANZUS Treaty is properly invoked.

John Howard, Prime Minister

We show our support for the United States in this fight because the fight against international terrorism is our fight. This is not only because of those Australians missing, believed killed, but also because of our belief in freedom, a belief we hold in common with the United States. It was an attack on all of us and all of ours.

Joining the strong international coalition to fight terrorism wherever it threatens democratic and peaceful nations, as suggested by Secretary Powell, is the right way to go. This will mean integrating more closely our intelligence and police agencies with their international counterparts. It will also mean providing appropriate military and police support to international counter-terrorist operations. A long-term counter-terrorist strategy and resource commitment are now required. The role of the SAS, of Commonwealth law enforcement and of intelligence and other agencies will be critical. They must have the tools to do their job in the modern terrorist environment.

Kim Beazley, Leader of the Opposition

… the terrorist attack on the United States, on New York and Washington, last Tuesday will mean that 11 September will be a date that lives on in infamy. It is a date that we will not forget; it is a date that we cannot forget; it is a date that we should never forget. It was a monstrous act, a premeditated and calculated mass murder aimed at ordinary people who were not just Americans but rather from a multitude of nations going about their ordinary lives. As others have said so eloquently, it constitutes an attack on decent people everywhere.

John Anderson, Leader of the National Party and Deputy Prime Minister

… these attacks on America are really attacks on freedom everywhere, and must be defended. I formally extend my condolences to the American people and to all of those who have been hurt here in Australia and across the world. It is my hope that the bond that has developed amongst the citizens of the world in reaction to this horror can be a springboard for a more tolerant and compassionate world.

Anna Burke, MP

A mood has descended over the civilised world: a complexion of grief, anger, resolve and unity. Australia joins the international expressions of solidarity, support and friendship with the United States. As it faces one of its greatest challenges in its proud history, the United States is not alone.

Julie Bishop, MP

The actions we saw on 11 September mark a turning point in human history, in the history of international relations, in terms of how one nation deals with another. We have not just turned a page; we have closed one chapter and we have begun a new chapter.

Kevin Rudd, MP

The attack on 11 September on the United States was a world-changing experience. The world will never be the same as it was on 10 September, following the events of 11 September. In some ways that will be a tragic thing; in other ways it may be a catalyst for a war on terrorism, which has been long overdue amongst the nations of the free world. This was an attack on the free world. It was an attack on our values, on our way of life, on our commitment to peace and on our commitment to democracy. 

Chris Pyne, MP

Despite some reluctance by the Australian Greens and the Australian Democrats to support paragraphs 6 and 7 in their original form, the same motion was also ultimately agreed to by the Australian Senate on the same day, with senators also standing for a minute’s silence. Select comments made in support of the motion follow:

Let us make no mistake: this was not just an attack on the United States but also a direct attack on the institutions of freedom, democracy and the rule of law that we in Australia, and so many people around the world, hold dear. If we truly value our own freedom, we must be ready to defend the freedom of others from the barbaric acts of terrorism we have witnessed in the United States. Those responsible must be found and punished.

Senator Robert Hill, Leader of the Government in the Senate

We need to acknowledge that the feelings of sorrow, fear and, in some cases, anger extend to many Australians. The immediacy of the images makes it feel so close. Courage, compassion and respect for the rule of law must guide us. We cannot turn our backs and we cannot strike out blindly. International cooperation and the role of the United Nations will be the key. There is no quick salve and justice may be slow. The difficulty of bringing those responsible to justice is frustrating, but I believe that the guilty will be punished and that justice will be done. It is important that grief does not ruin reason. 

Senator Natasha Stott Despoja, Leader of the Australian Democrats

The perpetrators, as many have said this afternoon, must be carefully and logically identified, pursued and punished. Their efforts to destroy the fabric of the community of the United States with their attacks in New York, Washington and Pennsylvania will not succeed. The world community—including the Australian community—has rallied behind the United States in this battle against terrorism. I believe that is where our strength lies: in that cohesion that we have to protect the fundamental freedoms of this world.

Senator Marise Payne

These were deliberate attacks against very powerful symbols of democracy and a country that is itself a powerful symbol of democracy. These attacks were designed to strike at the heart of all Western democracies that respect freedom and are governed by the rule of law. If these attacks were an attempt to damage or somehow change our view towards freedom and democracy, then these attacks will have failed.

Senator Joe Ludwig

In an address to a joint session of the US Congress on 20 September, President Bush characterised the attacks as an ‘act of war’ and made five demands of the Taliban in Afghanistan (pp. 1347­–1348), where it was believed those responsible for planning the attacks were hiding:

· deliver to United States authorities all the leaders of Al Qaida who hide in your land.

· release all foreign nationals, including American citizens, you have unjustly imprisoned.

· protect foreign journalists, diplomats, and aid workers in your country.

· close immediately and permanently every terrorist training camp in Afghanistan, and hand over every terrorist and every person in their support structure to appropriate authorities.

· give the United States full access to terrorist training camps, so we can make sure they are no longer operating.

The President made it clear that the demands were ‘not open to negotiation or discussion’ and warned that the Taliban must ‘act immediately’ to ‘hand over the terrorists’, or ‘share in their fate’.

This was followed by NATO determining on 2 October that Article 5 of the North Atlantic Treaty did indeed apply to the attacks, making it the first time in NATO’s 52-year history that Article 5 had been used. Two days later NATO agreed to a package of eight measures that would provide military, intelligence and logistical support to the US. This paved the way for NATO to mount its first-ever operations outside the Euro-Atlantic region and to use its military assets in support of Article 5 for the first time.

On 7 October 2001 the US and UK initiated military action in Afghanistan, and on 22 October, the first Australian troops departed to join the US-led operations. It would not be until July 2021 that the Australian Government announced that all Australian Defence Force personnel had left Afghanistan, ‘bringing our nation’s longest war to a close’.

Significant anniversaries since 2001

Every year since 2002 a ceremony is held on the anniversary of the attacks at the site of the World Trade Center in New York at which the names of those killed in the attacks are read aloud. Ten Australians were among the 2,977 people killed and some 343 firefighters and paramedics, 60 police officers and more than 700 employees from a single company died in the attack on the World Trade Center alone. Approximately 2,000 children overall lost a parent.

Every one of the victims who died on September 11th was the most important person on earth to somebody.

 President George W Bush, 11 December 2001

1st anniversary (2002)

In an address to an ecumenical service in Canberra on 11 September 2002, Prime Minister Howard said:

So as we gather in this Cathedral in our national capital to remember those terrible events, we grieve for those we lost, we grieve for the families of those ten Australians who died, we grieve with our American friends. We resolve to work ever closer together to root out evil, we resolve ever more firmly to extend the hand of Australian friendship and mateship to all Australians irrespective of their religious or ethnic background. We are Australians together. We are Australians and Americans and others together in the campaign against evil. We owe to the memory of those who died a year ago today a commitment to a continuance of the values of tolerance and decency which are above all else the foundations on which our society is built.

At a memorial service at the Church of the Epiphany in New York on 11 September 2002, Australia’s Minister for Foreign Affairs, Alexander Downer, stated:

11 September galvanised not just the United States, but Australia and New Zealand, prompting many to demonstrate their sense of shock, and affinity. In the end, our feelings of compassion and resolve have prevailed over those of fear, or horror, or retribution. This was, I am sure, in part because 11 September was an attack on the lifestyles and values that we hold so dear. The enormity of the crime was such that it brought home to us all the need to be resolute, deliberate, and measured – both as individuals and collectively. I believe that it is our common belief in individual rights, tolerance and diversity – the values which the perpetrators sought to undermine – that will help us to remember, and recover.

In a statement issued on 11 September 2002 the Leader of the Opposition, Simon Crean, observed:

September 11, 2001 is a day none of us will forget. Its first anniversary is a day for remembrance, reflection and resolve.

We reflect on our own sense of vulnerability from this new threat of global terrorism. September 11 was not just an attack on America, it was an attack on us all. It was an attack on the universal values of tolerance and freedom. Watching the people in the World Trade Centre Towers confront the prospect of their deaths had a profound impact on us all.

5th anniversary (2006)

Noting in a speech to parliament on 11 September 2006 that the 5th anniversary of the attacks was ‘an occasion for both remembrance and reaffirmation’, Prime Minister Howard remarked:

It is an occasion to remember the tragic loss of life, which included some 10 Australians. It is also an occasion to mark what an extraordinary change in the affairs of the world that terrorist attack ushered in.

The most important observation to make today is that fighting terrorism is a cause that involves us all. It is not just for the United States. It is not just for the United Kingdom or what used to be called the West. It is not just for Australia. It is for the entire world. If terrorism is to be defeated ultimately—and it will take years; let us not delude ourselves—it will require the marshalling, the commitment, the resolve, the resources and the spirit of men and women all around the world. It will involve the commitment of all faiths as well as people of no faith at all.

Terrorism is a threat to our way of life. The attack on 11 September was not just an attack on the people of the United States; it was an attack on the free people of the entire world. In our responses, let us understand the grim reality that, whereas in so many other cases prevention is better than cure, in relation to terrorism there is no cure. The only effective antidote against terrorism is to prevent it occurring in the first place.

In response, the Leader of the Opposition, Kim Beazley, commented:

We know that, as a result of our experience over these last five years, only through vigilance and courage will we win the battle against those who seek to destroy our society and the societies in which they are largely located. We know they may break our hearts, but they cannot diminish our resolve and our spirit.

We have to be resolute; we have to be effective; we have to be forthright; we have to be clever. This is a challenge that will outlast, I am afraid to say, the political careers of both the Prime Minister and me. It is a challenge that will go on through several generations. I can only hope that we get better and better at meeting it, that we have the same reserves of courage, resilience, love and affection that have been shown by survivors of September 11 five years ago …

10th anniversary (2011)

In marking the 10th anniversary of the attacks on 11 September 2011, Prime Minister Julia Gillard related some personal stories in an address to the National Commemoration Ceremony, concluding with the words:

And so on this day, on behalf of millions of Australians, I say this:

We do not forget. We never forget. United always in remembrance. United always in our resolve.

During a visit to Australia, the French Foreign Minister, Alain Juppé, said on 11 September 2011:

I am happy to sign this morning a tribute with my colleague, Kevin Rudd, about 9/11. The fight against terrorism is not finished and there is very much a cooperation between France and Australia in the struggle against this barbarian form of violence.

A joint statement released by Mr Juppé and the Australian Minister for Foreign Affairs, Kevin Rudd noted:

Mindful that this weekend marks the tenth anniversary of the terrorist attacks of 11 September, Mr Rudd and Mr Juppé reaffirmed their support for the victims of those abhorrent acts as well as the victims of terrorism throughout the world. While there have been some notable successes in combating terrorism, they agreed that the persistent terrorist threat reminds us of the importance of bilateral and multilateral cooperation in tackling international terrorist networks. Australia and France, together with other partners, will continue to respond decisively and swiftly to counter the threat of terrorism, at home and abroad.

15th anniversary (2016)

In March 2016, at a reception in Canberra for the National September 11 Memorial & Museum in New York, the US ambassador to Australia, John Berry, said:

Mr. Howard, the United States will never forget that your first action upon returning to Australia was to invoke, for the first time ever, the ANZUS treaty. Then and now the United States is immensely thankful for Australia’s unwavering commitment to the war on terrorism and extremism.

Australia and the United States are united against an evil that spreads distrust and hatred in an attempt to undermine democratic societies. Just as we are united by the values that come to the fore after too frequent attacks on the innocent – freedom, tolerance, and respect. It is these values that the terrorists hold in contempt. It is these values that nourish our alliance and our resolve.

On 11 September 2016 Prime Minister Malcolm Turnbull made the following remarks at a press conference:

That was an attack, a terrorist attack which changed the world. It was the largest mass casualty attack on American soil, of that kind. It saw John Howard invoke the ANZUS Treaty and it saw us stand then, as we stand today, shoulder to shoulder with free nations in the battle against terrorism. We have been shoulder-to-shoulder in that battle ever since.

We remember, when we mourn those who died in the 9/11 attacks we also honour the heroism of those who rushed to the aid of the victims in New York and in Washington—the heroes of that hour. We honour them. Next week in New York I will visit the 9/11 Memorial with Lucy and honour those who lost their lives both as victims of the attack and also as victims of the attack while they were seeking to rescue those who had been assaulted by that terrorist attack.

Australians killed

The Australians known to have died in the attacks were (in alphabetical order):

  • Kevin Dennis, 43, Queensland
  • Alberto Dominguez, 66, Sydney
  • Elisa Ferraina, 27, Sydney
  • Craig Gibson, 37, Sydney
  • Peter Gyulavary, 44, Victoria
  • Yvonne Kennedy, 62, Sydney
  • Andrew Knox, 29, Adelaide
  • Lesley Thomas, 40, NSW
  • Steve Tompsett, 39, Sydney
  • Leanne Whiteside, 31, Melbourne


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