This photograph of President George W. Bush greeting firefighters, police, and rescue personnel was taken by Eric Draper on September 14, 2001 in New York City. President Bush visited the first responders to the September 11, 2001 terrorist attacks on the World Trade Center, meeting the group at what was coined Ground Zero of the horrific events that occurred just days before. Bush toured Ground Zero and gave a speech offering support to the first responders.

This photograph of President Barack Obama delivering a statement on the death of Osama bin Laden was taken by Pete Souza on May 1, 2011. President Obama spoke live on television from the East Room late on May 1. Bin Laden was the leader of the terrorist group al Qaeda, who were responsible for the September 11, 2001 terrorist attacks on the World Trade Center in New York City, the Pentagon in Arlington, Virginia, and Flight 93, which crashed in Shanksville, Pennsylvania. His death was carried out through a military mission led by members of the United States Navy SEALs.

This photograph, taken by Paul Morse, shows President George W. Bush delivering an address to the nation from the Oval Office following the terrorist attacks on September 11, 2001. Bush delivered the live televised address that evening. Contributors to the speech included President Bush; speechwriters John McConnell, David Frum, Matthew Scully, and Michael J. Gerson; national security advisor Condoleezza Rice and her deputy assistant Stephen J. Hadley; and members of the White House communications team. In his remarks, Bush mourned the loss of American citizens yet asserted the strength of the nation, promised retribution for the perpetrators of the attacks and their supporters, and offered words of prayer.

In this photograph, taken by David Bohrer on September 18, 2001, President George W. Bush and Vice President Richard B. Cheney join White House staff to observe a moment of silence on the South Lawn honoring the victims of the terrorist attacks on September 11, 2001. The moment of silence ceremony has remained a tradition in the formal observation of September 11th at the White House. In 2002, President Bush designated September 11th as Patriot Day, a time that has been recognized through presidential proclamations as a national day of remembrance, prayer, and service.

In this photograph, taken by Paul Morse on September 18, 2001, President George W. Bush and Vice President Richard B. Cheney join White House staff to observe a moment of silence on the South Lawn honoring the victims of the terrorist attacks on September 11, 2001. The moment of silence ceremony has remained a tradition in the formal observation of September 11th at the White House. In 2002, President Bush designated September 11th as Patriot Day, a time that has been recognized through presidential proclamations as a national day of remembrance, prayer, and service.

In this photograph, taken by Kimberlee Hewitt on September 10, 2006, President George W. Bush and First Lady Laura Welch Bush participate in a wreath-laying ceremony at the north reflecting pool at the former site of the World Trade Center in New York, New York. President and Mrs. Bush paid their respects at the site to commemorate the fifth anniversary of the terrorist attacks that destroyed the twin towers of the World Trade Center on September 11, 2001. The National September 11 Memorial was later built on the site and dedicated on September 11, 2011. In May 2014, an adjacent museum was opened and dedicated by President Barack Obama.

In this photograph, President George W. Bush delivers a speech during the dedication ceremony for the National 9/11 Pentagon Memorial in Arlington, Virginia on the seventh anniversary of the terrorist attacks against the United States on September 11, 2001. Former Secretary of Defense Donald Rumsfeld can be seen seated behind the president. Designed by Julie Beckman and Keith Kaseman, the memorial honors the 184 victims who perished when the hijacked aircraft American Airlines Flight 77 crashed into the west side of the Pentagon. The outdoor memorial identifies victims by name and age, and includes illuminated water features to represent each victim. In 2002, President Bush designated September 11th as Patriot Day, a time that has been recognized through presidential proclamations as a national day of remembrance, prayer, and service. Presidents and first ladies typically commemorate the day through moment of silence observations on the White House South Lawn, and by attending remembrance ceremonies at sites affected by the terrorist attacks.

In this photograph, President George W. Bush, First Lady Laura Welch Bush, Vice President Richard B. Cheney, and Second Lady Lynne V. Cheney join White House staff for a moment of silence on the South Lawn in commemoration of the fourth anniversary of the terrorist attacks against the United States on September 11, 2001. In 2002, President Bush designated September 11th as Patriot Day, a time that has been recognized through presidential proclamations as a national day of remembrance, prayer, and service. Presidents and first ladies typically commemorate the day through moment of silence observations on the White House South Lawn, and by attending remembrance ceremonies at sites affected by the terrorist attacks.

In this photograph, taken by Paul Morse on September 9, 2005, President George W. Bush delivers remarks on the South Lawn during the presentation ceremony for the 9/11 Heroes Medal of Valor. The medal was created to honor 442 public safety officers, including firefighters, police officers, and emergency medical technicians, who died as a result of performing their duties in the immediate aftermath of the terrorist attacks on September 11, 2001. President Bush invited family members of the fallen officers to the South Lawn ceremony, where they were presented with the posthumous award.

In this photograph, President George W. Bush, First Lady Laura Welch Bush, Vice President Richard B. Cheney, and Second Lady Lynne V. Cheney join White House staff for a moment of silence on the South Lawn in commemoration of the second anniversary of the terrorist attacks against the United States on September 11, 2001. In 2002, President Bush designated September 11th as Patriot Day, a time that has been recognized through presidential proclamations as a national day of remembrance, prayer, and service. Presidents and first ladies typically commemorate the day through moment of silence observations on the White House South Lawn, and by attending remembrance ceremonies at sites affected by the terrorist attacks.

In this photograph, President George W. Bush, First Lady Laura Welch Bush, Vice President Richard B. Cheney, and Second Lady Lynne V. Cheney join victims' families for a moment of silence on the South Lawn in commemoration of the third anniversary of the terrorist attacks against the United States on September 11, 2001. In 2002, President Bush designated September 11th as Patriot Day, a time that has been recognized through presidential proclamations as a national day of remembrance, prayer, and service. Presidents and first ladies typically commemorate the day through moment of silence observations on the White House South Lawn, and by attending remembrance ceremonies at sites affected by the terrorist attacks.

In this photograph, President George W. Bush and First Lady Laura Welch Bush participate in a wreath-laying ceremony near the crash site for United Airlines Flight 93 in Somerset County, Pennsylvania, on the first anniversary of the terrorist attacks against the United States on September 11, 2001. Flight 93 was one of four airplanes hijacked by al-Qaida terrorists on September 11, 2001. Believed to be targeting the United States Capitol Building, the flight crashed into a field after passengers and crew attempted to regain control of the aircraft. Preliminary work for the Flight 93 National Memorial was completed on September 10, 2010, and the permanent memorial opened to the public on September 10, 2015. In 2002, President Bush designated September 11th as Patriot Day, a time that has been recognized through presidential proclamations as a national day of remembrance, prayer, and service. Presidents and first ladies typically commemorate the day through moment of silence observations on the White House South Lawn, and by attending remembrance ceremonies at sites affected by the terrorist attacks.

In this photograph, taken by Paul Morse on September 12, 2002, a group of firefighters unfurl a large American flag over the damaged Pentagon building in Arlington, Virginia following the terrorist attacks of September 11, 2001. The flag was displayed to encourage and inspire rescue workers as they searched the debris for survivors. On September 11, 2001, the hijacked aircraft American Airlines Flight 77 crashed into the west side of the Pentagon, resulting in 184 casualties. On September 11, 2008, President George W. Bush attended the dedication ceremony of the National 9/11 Pentagon Memorial, built to honor the victims of the attack.

This photograph was taken after executive office staff evacuated the White House following the terrorist attacks on the morning of September 11, 2001. Anita McBride, assistant to President George W. Bush, led a group of senior staff to continue operations from the DaimlerChrysler office building, where her husband Tim McBride, former aide to President George H. W. Bush, worked as director of government affairs. This photograph shows Ken Mehlman, deputy assistant to the president for political affairs (left), and Brad Blakeman, deputy assistant to the president for appointments and scheduling (third from left), at work at their temporary "command post" in the DaimlerChrysler offices with Israel Hernandez, deputy assistant to the president (second from left), and Joel D. Kaplan, special assistant to the president in the office of the chief of staff (right).

This photograph was taken after executive office staff evacuated the White House following the terrorist attacks on the morning of September 11, 2001. Anita McBride, assistant to President George W. Bush (pictured here at right), led a group of senior staff to continue operations from the DaimlerChrysler office building, where her husband Tim McBride, former aide to President George H. W. Bush, worked as director of government affairs. Also pictured in this photograph: Helen Mobley, director of presidential scheduling for correspondence and invitations (seated at left of Mrs. McBride), Josh Deckard, intern for the office of the White House chief of staff (standing behind at left), and Ashley Davis, deputy director of management and administration (standing behind at right).

This photograph was taken after executive office staff evacuated the White House following the terrorist attacks on the morning of September 11, 2001. Anita McBride, assistant to President George W. Bush, led a group of senior staff to continue operations from the DaimlerChrysler office building, where her husband Tim McBride, former aide to President George H. W. Bush, worked as director of government affairs. Here, Scott Stanzel, spokesperson for the White House Office of Media Affairs (far right), meets with communication staff in a DaimlerChrysler conference room. Pictured listening to Stanzel from left to right: Ken Lisaius, Wendy Nipper, and Jimmy Orr.

This photograph was taken from the corner of 17th Street and Pennsylvania Avenue near Lafayette Square in Washington, D.C. during the evacuation of executive office staff following the terrorist attacks on the morning of September 11, 2001. The evacuation notice applied to approximately 1,800 staff members who worked in the East and West Wings of the White House, the Old Executive Office Building (later rededicated as the Eisenhower Executive Office Building), the New Executive Office Building, and the Winder Building. Here, Anita McBride, assistant to President George W. Bush (center) confers with Mary Matalin, counselor to Vice President Richard B. Cheney. Shortly after this photograph was taken, Matalin joined Vice President Cheney in the Presidential Emergency Operations Center (PEOC) beneath the White House, and McBride and other senior White House transitioned into the DaimlerChrysler office building to continue their work for the day.

In this photograph taken on September 12, 2001, First Lady Laura Welch Bush listens to her East Wing staff members share what they experienced during the evacuation of the White House on September 11, 2001. Mrs. Bush learned of the suspected terrorist attacks during a visit to the United States Capitol Building the previous day, where she had intended to brief the the United States Senate Committee on Education on the White House Summit on Early Childhood Cognitive Development she had hosted that July.

In this photograph, White House staffers run toward the iron gates on West Executive Avenue following an evacuation order issued by the United States Secret Service after the terrorist attacks on the morning of September 11, 2001. In response to the threat of additional attacks, approximately 1,800 executive office employees were evacuated from the East and West Wings of the White House, the Old Executive Office Building (later rededicated as the Eisenhower Executive Office Building), the New Executive Office Building, and the Winder Building.

In this photograph, First Lady Laura Welch Bush speaks at the United States Capitol Building following the terrorist attacks on the World Trade Center in New York, New York on the morning of September 11, 2001. Mrs. Bush had planned on visiting the Capitol that day to brief the United States Senate Committee on Education on the White House Summit on Early Childhood Cognitive Development she had hosted that July. Here, Mrs. Bush is pictured standing between senators Judd Gregg of New Hampshire and Edward M. Kennedy of Massachusetts.

This photograph is of Mitchell Elias Daniels, Jr., director of the Office of Management and Budget during the George W. Bush administration. Daniels formerly served as White House director of political and intergovernmental affairs under President Ronald Reagan, and went on to serve as the governor of Indiana from 2005-2013. On September 11, 2001, Daniels hesitated to evacuate his office in the Old Executive Office Building (later rededicated as the Eisenhower Executive Office Building) and returned to work later that day from the Roosevelt Room in the West Wing.

This photograph was taken near Lafayette Square in Washington, D.C. during the evacuation of executive office staff following the terrorist attacks on the morning of September 11, 2001. The evacuation notice applied to approximately 1,800 staff members who worked in the East and West Wings of the White House, the Old Executive Office Building (later rededicated the Eisenhower Executive Office Building), the New Executive Office Building, and the Winder Building.

This photograph was taken on September 11, 2001. It shows West Wing staff gathered in the Navy Mess to watch media coverage of the unfolding terrorist attacks, and to await further instructions. The staff reported to the Navy Mess following the instructions of United States Secret Secret, and were later ordered to evacuate the building. Operated by the United States Navy, the Navy Mess is located near the Situation Room in the West Wing and serves as a cafeteria and restaurant for White House staff.

In this photograph, President George W. Bush delivers remarks from Emma E. Brooker Elementary School in Sarasota, Florida, following the terrorist attacks on the World Trade Center in New York city on the morning of September 11, 2001. The president was informed by his chief of staff Andy Card of the second strike on the towers while reading to children at the school. After delivering brief remarks at the school, Bush boarded Air Force One for his own protection, accompanied by roughly 65 advisors, security agents, and staff members. For the next several hours, President Bush worked from his office aboard Air Force One, where he monitored the crisis using the secure phone lines and televisions installed in the aircraft.

In this photograph, Vice President Richard B. Cheney meets with national security advisor Condoleezza Rice, deputy national security advisor Stephen J. Hadley, and other senior national security officials in the Presidential Emergency Operations Center (PEOC) following the terrorist attacks on the morning of September 11, 2001. From the secure facility beneath the White House, Vice President Cheney and the team of national security advisors communicated with President George W. Bush to monitor the crisis as it unfolded. President Bush received news of the suspected terrorist attacks while taking part in a reading demonstration at Emma E. Brooker Elementary School in Sarasota, Florida, and for the hours that followed worked from his office aboard Air Force One.