He was inaugurated just outside this rotunda on a blustery but bright Friday half a century ago today.  The previous Friday, January 13, 1961, the president-elect sent me a personal letter of thanks for the work we did out west on his campaign.
The letter was short, but it overflowed with optimism.  He knew the New Frontier he was about to lead would allow us to ‘make our country an even better place for our citizens to live, as well as to strengthen our country’s position of leadership in the world.’
That letter meant an awful lot to me as a 21-year-old.  It still does.  Today it hangs in the doorway of my office just down the hall from here – and just paces from the chamber where the three youngest Kennedy brothers served as United States Senators.  It is the first thing you see when you visit my office, and the last thing you see before you leave.
One week after John Kennedy signed that letter, the new president asked all of us to ask ourselves what we can do for our country.  That sense of service – that simple selflessness – inspired every American.  And it is that spirit we celebrate this afternoon.
Although his request of his fellow Americans – the ‘ask not’ line – has come to define his inaugural address, President Kennedy’s audience that day wasn’t just his countrymen.  Looking over the east front of the Capitol, the new president spoke to the world.
He forecast the great things allies can accomplish in cooperation – and he forewarned that there is little we can do divided.
He reminded us our time is better spent addressing the problems that unite us.  And he asked us to remember that ‘civility is not a sign of weakness.’
President Kennedy’s warnings were words the world needed to hear.  Today they are just as valuable for us to hear, here at home.
We cannot fully articulate the lessons of President Kennedy’s legacy in a single speech.  No single ceremony can appropriately account for all he did to make our country a better place to live – as he wrote me 50 years ago – or to strengthen America’s position of leadership in the world.
But as he implored of us on January 20, 1961: Let us begin.
Before I talk about President Kennedy’s tremendous legacy in the area of space exploration and innovation, I want to acknowledge the astronaut Buzz Aldrin, who is here today.
When he and Neil Armstrong became the first humans to touch the moon, our nation rejoiced not just because we were launching a new era of exploration and technology.  We cheered for more than just a stunning success for science.
When man first set foot on another world, we celebrated the fact that those first men were Americans.
As Armstrong leaped off that ladder, I remember hearing Walter Cronkite take care to note that the astronaut was a ‘38-year-old American.’ Because he was an American – a boy scout from Ohio and a pilot in our Navy – we all took pride.  America was moving mankind forward.  We were leaders.
The story of that journey did not begin when the Eagle landed.  It began years before: in the imaginations of Americans everywhere, and in laboratories and hangars in Florida and Texas.
But it took flight in this building, when President Kennedy asked Congress to commit to sending a man to the moon and returning him safely to Earth. 

And in a stadium in Houston where he told the world we were accepting this challenge precisely because it was daunting and difficult – because it was an opportunity we could not afford to put off until tomorrow.
He was right – it would be hard.  Not just the technology, but also the politics.  Opponents called his vision a ‘boondoggle’ and a ‘science-fiction stunt.’  But President Kennedy knew from the start what was waiting for America in the stars.
On his first day as president, he invited the crowd gathered here at the Capitol – and the millions who were watching and listening – to join him in exploring the worlds beyond ours and seizing the wonders of science.
And throughout the brief time he was our nation’s leader, he insisted that our nation lead the sprint to conquer space – and that we finish that race first.
On his last full day as president, as he dedicated a medical space research center in San Antonio, President Kennedy reaffirmed his commitment to corralling the full promise of the universe.  ‘I think the United States should be a leader,’ he said.  America, he demanded, ‘should be second to none.’
In the first words of the inaugural address we celebrate today, Kennedy recalled the nation’s founding nearly two centuries earlier and observed, ‘The world is very different now.’  Half a century later, the world is again very different.
Solar energy is a reality in states like Nevada and across the country because of the science that started in space.
The water we drink is cleaner.  Our oceans are healthier.  We diagnose cancer sooner.  All because of the discoveries our space program has made possible.
Our wounded warriors wear better and stronger artificial limbs.  Citizens of the world are safer from land mines.  Firefighters can better track forest fires, and are safer when they fight them.  Airplanes fly smarter, and even golf balls fly farther.  All because when many others pulled back and doubted, President Kennedy kept pushing forward – forward with faith.
We’ve all seen the picture that captured Armstrong’s small step for man – the imprint of his American boot in the dust of the moon.
But you don’t need to scale the heavens to know the meaning or feel the force of space and science in our lives.  Look all around you.  That is President John Fitzgerald Kennedy’s footprint on our future.