It was a clear and seemingly normal Tuesday morning in America. The New York City buses and subway trains were running on schedule. President George W. Bush sat in a Florida classroom, visiting with elementary students. Todd Beamer, Sandy Bradshaw and 43 others boarded United Flight 93, bound for California. It was business as usual at the World Trade Center as well, where nearly 50,000 people were employed. All in all it was an uneventful September morning. And then the clock ticked 8:46 a.m. Thats when a hijacked American Airlines jet traveling nearly 500 miles per hour and loaded with 10,000 gallons of fuel crashed into the north tower of the World Trade Center. America as it had been quickly and without warning emphatically changed. Eighteen minutes after the first plane struck, a second jetliner roared above the New York City skyline before it ominously turned toward the south tower. The resulting collision produced a massive fireball as the plane disappeared from view and glass and concrete rained down. Everyone on board was killed, as were several inside the building. Dark, thick smoke billowed from the twin towers. The nation was under attack, but the enemy wasnt done yet. An hour after the first Boeing 767 crashed into the north tower, a third plane zoomed low over Washington, D.C. before it crashed into the west side of the Pentagon, the nation's military headquarters, killing 64 people aboard and 125 people inside the building. As emergency personnel responded to the horrifying scene in the nations capital, police and firefighters in New York City were rushing into the crippled twin towers in an attempt to evacuate the buildings. But just 15 minutes later, as a stunned nation watched, the south tower, unable to withstand the intense heat of the inferno raging inside, collapsed in on itself. All 110 stories crashed to the ground in a torrent of concrete, steel and dust. The north tower would follow suit less than an hour later. A fourth plane, United Flight 93, had taken off from Newark International Airport in New Jersey that morning. It was hijacked shortly after by a small group of Islamic extremists wielding small knives or box cutters smuggled through airport security. Through cell phone communications, the passengers on board learned of the attacks in New York. A small group formed a plan to ensure that their flight would not ultimately become a guided missile as had the jets in New York. Todd Beamer was one of those passengers, and was heard on an open line, talking to his fellow passengers before their attack on the hijackers began, saying simply, Lets roll. They are thought to have stormed the cockpit, and United 93 is believed to have flipped over before it hurled toward the ground, crashing in a field in rural Pennsylvania and killing all 45 people aboard. Officials later said the hijackers were likely targeting sites in Washington, D.C., possibly the White House or Capitol. More than 2,600 people lost their lives in the attacks on New York City, including 343 New York firefighters, in what was later determined to be a well coordinated terrorist attack perpetrated by 19 hijackers, many from Saudi Arabia working on orders from the then little known terrorist group al-Qaeda and its leader, a Saudi Arabian native named Osama bin Laden. In all, 2,975 people lost their lives, the most of any attack on American soil, including Pearl Harbor. The response from the federal government was quick. President Bush addressed the nation that evening, acknowledging the attacks as a strike against Americas ideals of democracy and a free society. Today, our fellow citizens, our way of life, our very freedom came under attack in a series of deliberate and deadly terrorist acts, the President said. The victims were in airplanes or in their offices: secretaries, business men and women, military and federal workers, moms and dads, friends and neighbors. Thousands of lives were suddenly ended by evil, despicable acts of terror. President Bush directed the full force of the federal governments intelligence and law enforcement agencies to track down those responsible for the attacks, which officials quickly traced back to al-Qaeda. The nations lawmakers, meanwhile, dispensed with politics and displayed a show of solidarity. Sen. Mitch McConnell, a Republican from Kentucky, was at home when he heard of the attacks. Like most Americans, I was glued to the television and watched the attacks unfold before my eyes, he said. I saw the second plane go into the second tower. McConnell said there was no mistaking what had happened that day. America had been drawn into a new kind of war, with a new kind of enemy. I saw the reports about the plane striking the Pentagon and the plane that went down in Pennsylvania that we now believe was intended to hit the Capitol, he continued. By the end of the day it was clear America was at war, and things would never be the same. I joined my colleagues on the Capitol steps to sing God Bless America to show the nation and the world that our government was united and unafraid. Less than a month after the attacks, the American military led an international force to begin Operation Enduring Freedom with the aim of toppling the Taliban-led government in Afghanistan, a regime that gave safe harbor to bin Laden and al-Qaeda in the years prior to the September 11 attacks. But President Bush was also clear that the war on terror was a broad conflict and not exclusive to the Taliban. Every nation has a choice to make, President Bush told the nation during an address on October 7, 2001. In this conflict, there is no neutral ground. If any government sponsors the outlaws and killers of innocents, they have become outlaws and murderers themselves. And they will take that lonely path at their own peril. The Talibans grip on power fell quickly, with their leader, Mullah Omar, going into hiding. Eventually, Hamid Karzai gained power over a new democratic government, but Americas presence in the war-torn country remains even today, 10 years after the tragedy of September 11, 2001. By March 2003 America was led into a second conflict, this time in Iraq where the Arab countrys dictator, Saddam Hussein, fell from power following an American-led assault on Baghdad, though an American presence also presently remains there as well. The search for al-Qaedas leader bore little fruit in the years following the September 11 attacks. Many estimates placed bin Laden in the lawless border region of Pakistan and Afghanistan where American drones continually launched missile attacks against terrorist targets. Then, in April 2011, a team of Navy SEALS acting on orders from President Barack Obama raided a sprawling compound in Abbottabad, Pakistan 30 miles outside of the capital of Islamabad. After a fire fight that lasted nearly 40 minutes, bin Laden lie dead, bringing to a close at least one chapter of the aftermath of 9/11. As America forges ahead, the nations people continue to look back on that day 10 years ago that altered the national consciousness. During an address in 2010 to mark the 9th anniversary of the attacks, President Obama paid homage to those who lost their lives, but noted that America must push ahead with the same resilience and fortitude that our nation displayed in the days that followed. So let us grieve for those weve lost, the President said, honor those who have sacrificed, and do our best to live up to the values we share on this day, and every day that follows.