It’s been 36 days since terrorists attacked America. More than a month — but the images are just as strong, the pain just as real, and the shock — the horror — still resonates. Yet, somehow, I think, despite everything, in spite of our collective grief, Americans are united in our conviction to thwart terrorism, to defend our nation, to take every step we can so this will never happen again.

Before September 11, civil aviation was the sound — it was the symbol of commerce.

From the days of Charles Lindbergh — who saw aviation as part of the continuum of human endeavor — Americans have recognized aviation’s enormous potential for fostering economic growth and prosperity, for enriching our lives.

On September 11, the world changed. Terrorists turned tools of commerce —instruments of unity — into weapons of hate.

President Bush has made it abundantly clear, the United States regards the attacks as an act of war…not only as an assault on America’s financial and political capitals, but as an attack on freedom itself.

We know the world changed forever on September 11. Acts “outside the bounds of human behavior or imagination” challenged all our assumptions. The acts of September 11 changed the way we view national security and aviation security. It reordered our priorities.

The new world began on September 11. It was a day like any other late summer day — it was perfect for flying, what some pilots call “severe clear.” The peak demands of summer were behind us. Air traffic controllers expected a routine, on-time day. Four-thousand-eight-hundred-and-seventy-three aircraft were operating in U.S. airspace. The day — and lives — were shattered at 8:45 a.m. when the first jet struck the World Trade Center.

At the first suspicion of a hijacking, we notified all air traffic facilities. From our control towers and radar screens the developing picture became more alarming. The first step was to stop traffic into and out of New York and Boston. Next, a national ground stop was issued, that is, no civil aircraft in the U.S. could take off.

After speaking with Secretary Mineta, controllers told all airborne aircraft to land at the nearest airport. Within four minutes, controllers directed 700 planes to safe landings. Another 2,800 planes returned to safe ground in 54 minutes. By 12:16 p.m., within hours of the first attack, U.S. airspace was clear of traffic.

The clearest image in my mind — standing in the FAA Operations Center and watching the electronic map of the United States showing all airborne aircraft. Thousands of airplanes. Then fewer. And fewer. And fewer. And finally, the map was blank.

One journalist who was airborne at the time wrote that the controllers, the systems people, and management supporting them did their jobs and brought tens of thousands of Americans safely back to earth.

Some airports handled as many planes on that day as they would normally see in a week. Gander International Airport in Canada, for one, had 34 transatlantic flights diverted to this town of 10,400 people. That town — and others like it — saw their populations swell. They opened schools, parish halls, and their hearts to thousands of stranded travelers.

There are countless stories like those — stories of spontaneous humanity and acts of kindness, stories of generosity, and stories of remarkable courage. They have moved us as a nation profoundly. And it is those acts of courage that have inspired all of us in the long days since September 11. I know when I visit FAA facilities, when I meet with employees, there is a renewed sense of commitment and passion for our mission and an unwavering resolve to make our nation’s aviation system safe and secure.

In the first days after September 11, the aviation community struggled with a number of challenges. First, of course, was reopening airports and getting America flying again. At the same time, we had to do this against the backdrop of equally unprecedented — and uncertain — security risks.

We needed to redefine our world through the prism of September 11. And we needed to meet the challenges on several fronts. If I can draw an analogy that President Bush has used about fighting the war on terrorism. He said it must be done through diplomatic, military, financial, and investigative actions. Engineers call this a systems approach. The FAA and the aviation community are meeting the aviation security challenges with a systems approach as well.

We have looked at the threats from several different perspectives and are convinced that our response lies on multiple levels. The first level is early identification and thus immediate prevention of potential threats — sharing information across key government agencies, working with airline databases, and background checks on employees with access to secure areas of airports. Since September 11 we have experienced constant sharing of information, specifically with intelligence and law enforcement agencies. Still, the longer-term challenge is a central database against which passengers and employees can be checked.

In terms of employees, legislation passed last year gave us the ability to do criminal history background checks of new employees with access to secure areas of our largest airports. That was a good first step. Immediately after the attacks, we required re-validation of the identification of everyone with airport access badges and also matched them against FBI watch lists.

But we must do more. I am directing that a criminal history check be done on all airline and airport employees with access to secure areas. I want to particularly acknowledge Director Robert Mueller of the FBI and Director Kay Cole James of the Office of Personnel Management who have committed the necessary resources to take this on. For our part, federal dollars are available — through the Airport Improvement Program — for airports to purchase fingerprinting machines that will speed up the background checks.

From intelligence information and background checks, the first goal — the first level of defense — is clearly to keep terrorists away from the airport. The second level is screening — or detection — to prevent access to the airplane. It includes the expanded Computer Assisted Passenger Prescreening System, new technologies to detect plastic weapons, and greater use of explosives detection equipment.

Before September 11, Congress gave us the initial resources to put in explosives detection technology at the largest commercial service airports. But, in today’s world, we must accelerate the program. The goal for all of us must be the 100 percent screening of every checked bag. The great challenge is how rapidly can the screening equipment be produced. I can tell you that every machine that is produced will be deployed immediately.

That brings me to the third level — preventing unauthorized access to the cockpit. This was a priority for Secretary Mineta. We needed the cockpits secured quickly. We had to cut through red tape. And we did. In addition, President Bush matched this commitment with a $500 million dollar fund to finance aircraft modifications.

Airlines are moving swiftly. As of today, the major airlines have modified the cockpit doors on nearly 50 percent of their combined fleet. American Airlines, for one, began almost immediately and is strengthening the cockpits of 50 to 60 aircraft every day. United said it will have its modifications completed this Sunday. JetBlue is installing bullet-proof doors. Work is getting done — quickly and well.

Looking ahead, Secretary Mineta created a $20 million dollar fund to explore new technologies to improve aircraft security. Airlines can develop systems to provide warnings from the cabin to the cockpit. Or they can test a new, backup transponder as well as camera surveillance. The grants can be used to test any new technology that leads to safer, more secure aircraft. We’ve already received applications from 13 airlines — regional and major carriers alike — and more are on the way.

Critical to securing the cockpit is an expanded Federal Air Marshals program. In the days right after September 11, we dramatically expanded this program.

All of this adds up to an integrated security approach. Every measure is important and must work together to create a seamless web of security. And, most important, we must stay as committed to this task tomorrow — and into the future — as we are today. The FAA — the Department of Transportation — cannot do this alone. Each of us — airlines and airports — has obligations to fulfill. In the words of one airline CEO, “There is a moral imperative to do the right thing.”

It is a new world for this industry and our nation. But in a column written shortly after the attacks, Thomas Friedman reminds us that —“unable to actually imprison us, these terrorists want us to imprison ourselves.” We must — each of us — do what needs to be done to ensure that does not happen.

We cannot regain our innocence we lost on September 11, but we will — we must — regain confidence in the safety of air travel.

Aviation is too important to our nation, our economy, and our way of life.

Americans have long known that “eternal vigilance is the price of liberty.” Now, we know, it is the price of mobility.