Today, Barack Obama and Dmitry Medvedev meet in Prague to sign an agreement that will eliminate more than 1,000 large nuclear bombs from the Earth. Ho-hum! Commentators are carping that this development is not splashy or dramatic enough. Quite the contrary: it is magnificent news for our world.

When historians look back on the present generation, they will say that there were three trends of historic import – and none involve the effluvial trivia that dominate most contemporary discourse.

One trend of historic import is the spread of democracy, a sanguine development which seemed impossible as recently as the 1980s. The second is the rapid decline of global poverty – an improvement barely remarked upon in the West, because it isn’t happening there, and violates the chic-pessimism script preferred by tastemakers. China has moved 220 million people, nearly the population of the United States, out of poverty in a single generation. This production-and-output achievement is every bit the equal of America’s production-and-output achievement to win World War II. Poverty is declining in many though of course not all other developing nations.

The third great development of the present generation is steady decline in the world’s inventory of Armageddon weapons. According to estimates from the Federation of American Scientists, at the peak, in the mid-1980s, the United States and old Soviet Union possessed 80,000 nuclear warheads – sufficient to end human life, if not life on Earth.

Following a quarter-century succession of agreements backed by Democratic and Republican presidents alike in the United States, and reformers and zealots alike in Russia, the total is down to about 15,500 nuclear warheads. That is still too high. But when else exactly in history has fourth-fifths of any category of military power voluntarily been given up, to say nothing of within a single generation?

Today’s agreement binds the United States and Russia to a further reduction of about 1,600 thermonuclear devices, and the ones to be eliminated are the worst kind – “strategic” warheads up to 125 times as powerful as the atomic explosive dropped on Hiroshima. In the 1980s, each side possessed about 10,000 strategic bombs of extreme destructive force. Under the terms of today’s agreement, each side will be limited to 1,550, representing an 85 percent reduction in the worst category of nuclear threat.

The Prague agreement further sets the stage for a renewed push for nonproliferation — unfortunately, not likely to succeed in the short term — and for U.S.-Russian negotiations toward a sharp reduction in short-range, Hiroshima-class “tactical” nuclear weapons. There may be no realistic means to get Iran or North Korea to abandon nuclear-weapon efforts. But it is quite realistic to hope the United States and Russia will agree to more cuts in tactical nuclear arms: Moscow has already signaled its desire for this. Tactical nuclear munitions don’t engage public or political attention, because a single one cannot incinerate a city. But because tactical nuclear bombs are so numerous, reducing them is important, too.

Once today’s agreement takes force, the United States and Russia combined will have about 3,000 strategic nuclear devices and about 11,000 tactical bombs – far less than the two sides possessed at the height of the Cold War. Future historians may express amazement that so little heed has been paid to such reduction: though nuclear arms are by a huge margin the worst threat to human life.

Nor is much attention paid to related treaties by which Washington and Moscow have agreed to keep most nuclear warheads in storage – most of today’s bombs could not be fired by accident because it would take days or weeks to re-initialize them; agreed drastically to reduce the number of ICBMs, the missiles that carry the worst kinds of nuclear warheads; agreed to halt development of new ICBMs; and agreed it make it harder, though not impossible, to target ICBMs against cities.

Grousing that today’s Prague agreement somehow isn’t impressive enough, because it represents only one phase in reducing the nuclear-war threat, betrays a lack of any sense of history. Today’s agreement is magnificent: showing the leaders of the United States and Russian Federation share a positive vision of walking the world back from the brink of midnight.

As president, Jimmy Carter supposed that nuclear warheads could be reduced until each side possessed only 100: he felt that would be ample to insure against attack. Last year, Obama said he sought a “world without nuclear weapons.” Neither of these idealistic goals may come to pass. It’s not even clear a world without nuclear weapons would be desirable. For 65 years, nuclear deterrence has prevented great-powers war: the maintenance of small nuclear inventories sustains that deterrence.

But it is undeniable that shrinking the doomsday arsenal is a global good, and today’s agreement is another step. For two decades, nuclear-warhead facilities in the United States and Russia have run in reverse, disassembling bombs rather than making them. Today’s agreement gives the bomb-disassembly facilities a few years’ more business. If only every day brought such welcome news.