Let me ask you all a question. How much weapons-grade nuclear material do you think it would take to level a city the size of San Francisco? How many of you think it would be an amount about the size of this suitcase? OK. And how about this minibus?

All right. Well actually, under the right circumstances, an amount of highly enriched uranium about the size of your morning latte would be enough to kill 100,000 people instantly. Hundreds of thousands of others would become horribly ill, and parts of the city would be uninhabitable for years, if not for decades.

But you can forget that nuclear latte, because today's nuclear weapons are hundreds of times more powerful even than those we dropped on Hiroshima and Nagasaki. And even a limited nuclear war involving, say, tens of nuclear weapons, could lead to the end of all life on the planet.

So it's really important that you know that right now we have over 15,000 nuclear weapons in the hands of nine nations. And if you live in a city or near a military facility, one is likely pointed right at you. In fact, if you live in any of the rural areas where nuclear weapons are stored globally, one is likely pointed at you. About 1,800 of these weapons are on high alert, which means they can be launched within 15 minutes of a presidential command.

So I know this is a bummer of an issue, and maybe you have that -- what was it? -- psychic fatigue that we heard about a little bit earlier. So I'm going to switch gears for just a second, and I'm going to talk about my imaginary friend, who I like to think of as Jasmine, just for a moment.

Jasmine, at the age of 25, is part of a generation that is more politically and socially engaged than anything we've seen in 50 years. She and her friends think of themselves as change agents and leaders and activists. I think of them as Generation Possible. They regularly protest about the issues they care about, but nuclear weapons are not one of them, which makes sense, because Jasmine was born in 1991, at the end of the Cold War. So she didn't grow up hearing a lot about nuclear weapons. She never had to duck and cover under her desk at school. For Jasmine, a fallout shelter is an app in the Android store. Nuclear weapons help win games. And that is really a shame, because right now, we need Generation Possible to help us make some really important decisions about nuclear weapons.

For instance, will we further reduce our nuclear arsenals globally, or will we spend billions, maybe a trillion dollars, to modernize them so they last throughout the 21st century, so that by the time Jasmine is my age, she's talking to her children and maybe even her grandchildren about the threat of nuclear holocaust? And if you're paying any attention at all to cyberthreats, or, for instance, if you've read about the Stuxnet virus or, for God's sake, if you've ever had an email account or a Yahoo account or a phone hacked, you can imagine the whole new world of hurt that could be triggered by modernization in a period of cyberwarfare.

Now, if you're paying attention to the money, a trillion dollars could go a long way to feeding and educating and employing people, all of which could reduce the threat of nuclear war to begin with. So --

(Applause)

This is really crucial right now, because nuclear weapons -- they're vulnerable. We have solid evidence that terrorists are trying to get ahold of them. Just this last spring, when four retirees and two taxi drivers were arrested in the Republic of Georgia for trying to sell nuclear materials for 200 million dollars, they demonstrated that the black market for this stuff is alive and well. And it's really important, because there have been dozens of accidents involving nuclear weapons, and I bet most of us have never heard anything about them.

Just here in the United States, we've dropped nuclear weapons on the Carolinas twice. In one case, one of the bombs, which fell out of an Air Force plane, didn't detonate because the nuclear core was stored somewhere else on the plane. In another case, the weapon did arm when it hit the ground, and five of the switches designed to keep it from detonating failed. Luckily, the sixth one didn't. But if that's not enough to get your attention, there was the 1995 Black Brant incident. That's when Russian radar technicians saw what they thought was a US nuclear missile streaking towards Russian airspace. It later turned out to be a Norwegian rocket collecting data about the northern lights. But at that time, Russian President Boris Yeltsin came within five minutes of launching a full-scale retaliatory nuclear attack against the United States.

So, most of the world's nuclear nations have committed to getting rid of these weapons of mass destruction. But consider this: the treaty on the nonproliferation of nuclear weapons, which is the most widely adopted arms control treaty in history with 190 signatories, sets no specific date by which the world's nuclear-armed nations will get rid of their nuclear weapons.

Now, when John F. Kennedy sent a man to the moon and decided to bring him back, or decided to do both those things, he didn't say, "Hey, whenever you guys get to it." He gave us a deadline. He gave us a challenge that would have been incredible just a few years earlier. And with that challenge, he inspired scientists and marketers, astronauts and schoolteachers. He gave us a vision. But along with that vision, he also tried to give us -- and most people don't know this, either -- he tried to give us a partner in the form of our fiercest Cold War rival, the Soviet Union. Because part of Kennedy's vision for the Apollo program was that it be a cooperation, not a competition, with the Soviets. And apparently, Nikita Khrushchev, the Soviet Premier, agreed. But before that cooperation could be realized, Kennedy was assassinated, and that part of the vision was deferred.

But the promise of joint innovation between these two nuclear superpowers wasn't totally extinguished. Because in 1991, which is the year that Jasmine was born and the Soviet Union fell, these two nations engaged in a project that genuinely does seem incredible today in the truest sense of that word, which is that the US sent cash to the Russians when they needed it most, to secure loose nuclear materials and to employ out-of-work nuclear scientists. They worked alongside American scientists to convert weapons-grade uranium into the type of fuel that can be used for nuclear power instead. They called it, "Megatons to Megawatts." So the result is that for over 20 years, our two nations had a program that meant that one in 10 lightbulbs in the United States was essentially fueled by former Russian warheads.

So, together these two nations did something truly audacious. But the good news is, the global community has the chance to do something just as audacious today. To get rid of nuclear weapons and to end the supply of the materials required to produce them, some experts tell me would take 30 years. It would take a renaissance of sorts, the kinds of innovation that, for better or worse, underpinned both the Manhattan Project, which gave rise to nuclear weapons, and the Megatons to Megawatts program. It would take design constraints. These are fundamental to creativity, things like a platform for international collaboration; a date certain, which is a forcing mechanism; and a positive vision that inspires action. It would take us to 2045.

Now, 2045 happens to be the 100th anniversary of the birth of nuclear weapons in the New Mexico desert. But it's also an important date for another reason. It's predicted to be the advent of the singularity, a new moment in human development, where the lines between artificial intelligence and human intelligence blur, where computing and consciousness become almost indistinguishable and advanced technologies help us solve the 21st century's greatest problems: hunger, energy, poverty, ushering in an era of abundance. And we all get to go to space on our way to becoming a multi-planetary species.

Now, the people who really believe this vision are the first to say they don't yet know precisely how we're going to get there. But the values behind their vision and the willingness to ask "How might we?" have inspired a generation of innovators. They're working backward from the outcomes they want, using the creative problem-solving methods of collaborative design. They're busting through obstacles. They're redefining what we all consider possible.

But here's the thing: that vision of abundance isn't compatible with a world that still relies on a 20th-century nuclear doctrine called "mutually assured destruction." It has to be about building the foundations for the 22nd century. It has to be about strategies for mutually assured prosperity or, at the very least, mutually assured survival.

Now, every day, I get to meet people who are real pioneers in the field of nuclear threats. As you can see, many of them are young women, and they're doing fiercely interesting stuff, like Mareena Robinson Snowden here, who is developing new ways, better ways, to detect nuclear warheads, which will help us overcome a critical hurdle to international disarmament. Or Melissa Hanham, who is using satellite imaging to make sense of what's going on around far-flung nuclear sites. Or we have Beatrice Fihn in Europe, who has been campaigning to make nuclear weapons illegal in international courts of law, and just won a big victory at the UN last week.

(Applause)

And yet, and yet, with all of our talk in this culture about moon shots, too few members of Generation Possible and those of us who mentor them are taking on nuclear weapons. It's as if there's a taboo. But I remember something Kennedy said that has really stuck with me, and that is something to the effect that humans can be as big as the solutions to all the problems we've created. No problem of human destiny, he said, is beyond human beings. I believe that. And I bet a lot of you here believe that, too. And I know Generation Possible believes it.

So it's time to commit to a date. Let's end the nuclear weapons chapter on the 100th anniversary of its inception. After all, by 2045, we will have held billions of people hostage to the threat of nuclear annihilation. Surely, 100 years will have been enough. Surely, a century of economic development and the development of military strategy will have given us better ways to manage global conflict. Surely, if ever there was a global moon shot worth supporting, this is it.

Now, in the face of real threats -- for instance, North Korea's recent nuclear weapons tests, which fly in the face of sanctions -- reasonable people disagree about whether we should maintain some number of nuclear weapons to deter aggression. But the question is: What's the magic number? Is it a thousand? Is it a hundred? Ten? And then we have to ask: Who should be responsible for them? I think we can agree, however, that having 15,000 of them represents a greater global threat to Jasmine's generation than a promise.

So it's time we make a promise of a world in which we've broken the stranglehold that nuclear weapons have on our imaginations; in which we invest in the creative solutions that come from working backward from the future we desperately want, rather than plodding forward from a present that brings all of the mental models and biases of the past with it. It's time we pledge our resources as leaders across the spectrum to work on this old problem in new ways, to ask, "How might we?" How might we make good on a promise of greater security for Jasmine's generation in a world beyond nuclear weapons? I truly hope you will join us.

Thank you.