The earthquake, just off the coast, was swift and terrible, registering almost 9.0. Even more deadly were the 15-metre tsunami and the raging fires that soon followed. Thousands of people died or were swept out to sea, their homes reduced to mountains of rubble.
And what's more, it had hit what seemed like the most careful, prosperous and well-prepared country, the one most respected for doing things right. The moment of chaos nearly led to societal breakdown as great cities were reduced to panic and helplessness. People began to have serious doubts about their core beliefs. There was no more faith in the old certainties.
So it was in Lisbon in 1755. That earthquake, one of the worst in history, did terrible damage to Portugal, wiping out almost a third of its population and helping end its moment of economic supremacy. But it had an even more dramatic effect on the way the world thought of itself.
Across the Western world, the events of 1755 seemed to disprove everything people had held true about the dominion of man over nature, the benign power of God and the authority of the Church. It was the Lisbon quake that provoked thinkers like Kant, Rousseau and Voltaire to abandon religious authority and begin developing a human-driven thought and politics.
It triggered the chain of events that led Europeans to expel the Church and rely on their own political and technological inventions. By teaching people that the heavens were against them, it allowed civilization to become supreme and the greatest age of human progress to take place. It was an earthquake with a lasting lesson.
And so it is in Japan in 2011. The Japanese catastrophe has shocked the world, even though its death toll is an order of magnitude lower than the great quakes of China in 1976 and South Asia in 2004. It was much less deadly, despite being a far stronger quake, because the Japanese were so well prepared, so thoroughly technologically defended and trained to deal with the tyranny of nature. On that level, while the deaths and human tragedies that have taken place are horrendous and heartbreaking, there are reasons to give thanks.
Japan's government building codes, safety regulations, early-warning systems, shelter networks and safety-training regimes have saved tens of thousands of lives or more. The weaker Indian Ocean tsunami of December, 2004, killed 230,000 people; the Japanese toll will barely break the five-figure mark.
But what has stopped all of us in our tracks, and seemingly changed many opinions, is not the natural disaster but the catastrophic failure of the Fukushima nuclear plant. The exploding, steaming, uncontrolled electrical-generation complex is the image that has shocked the world.
Though it is a far less deadly event than the seismic shock, the ocean flood or, now, the ill-timed blizzard that has struck northern Japan, the drama at the reactor has galvanized us. And instead of turning against nature's cruelty, we are turning against the technology designed to fend it off.
This comes at exactly the moment when the world needs many more nuclear reactors and other non-carbon-emitting sources of power. The Japanese factory has shifted our balance of fear. Two weeks ago, it was the Earth that we dreaded the most - the spectre of fast-rising temperatures and ocean levels - and almost everyone agreed it was worth making some investments and taking some risks to alleviate the threat.
Though governments have famously failed to agree on a comprehensive plan to get carbon emissions under control, great strides were being made in many countries, most notably among the emerging powers of Asia. And those plans relied heavily on building scores of nuclear-power plants to displace coal, in order to fuel the next wave of growth in ways that wouldn't clot the upper atmosphere.
A few days of Japanese television has shifted the world's balance of fear: Suddenly, we are living in terror not of nature's caprices but of our own inventions.
Days after the earthquake, a cascade of nations announced plans to suspend or drop nuclear-power projects. Most visible were the European Union nations, whose climate-change commitments will make large nuclear-construction programs vital. Remember that wind-power projects, such as Germany's, rely on nuclear reactors to provide power when the wind is down.
But more alarming was the sudden shift in the industrializing nations of the developing world. China suspended all current construction of nuclear reactors - at least 25 major projects. In India, environment minister Jairam Ramesh planned to review and possibly scrap all nuclear projects along the west coast, including a vital facility planned at Ratnagiri, south of Mumbai.
These countries were not building nuclear plants to save mo-
ney: They are considerably more expensive than gas or coal plants. China and India and a dozen other countries are going nuclear because they want to meet their climate-change commitments and reduce atmospheric pollution. For these governments, going nuclear was ecologically revolutionary.
It may be possible in Europe and North America to talk about reducing consumer demand for electricity and using alternatives instead of nukes. But none of that applies in Asia, Africa or South America, where the most pressing demand in the next two decades will be to turn three billion poor or impoverished people into energy consumers - ideally, high-efficiency, low-waste consumers, but certainly people able to have street lighting and refrigerators.
To do this without nuclear power would either be ecologically catastrophic, because it would rely on more coal-fired generation than the world has seen, or murderously inhumane, because it would raise energy prices to levels that would keep people in terrible poverty.
The world needs two things now: fewer carbon emissions, and a growing supply of energy at a low cost. By accomplishing both, nuclear power, even factoring in disasters, can save millions of lives.
Some leading environmentalists this week immediately recognized the danger of abandoning nuclear power. The British arch-Green activist George Monbiot wrote a cri de coeur on Thursday urging countries to stay with nuclear: "Even when nuclear power plants go horribly wrong, they do less damage to the planet and its people than coal-burning stations operating normally," he wrote, rightly.
"Coal, the most carbon-dense of fossil fuels, is the primary driver of human-caused climate change. If its combustion is not curtailed, it could kill millions of times more people than nuclear power plants have done so far. … Abandoning nuclear power as an option narrows our choices just when we need to be thinking as broadly as possible."
The Japanese nuclear disaster is bad: Many people could be killed, and the area immediately surrounding the plant could become uninhabitable. But it could not become a Chernobyl-style disaster, with a carbon fire spreading radiation beyond the plant's vicinity and injuring thousands. No reactors today are built that way.
On the other hand, it is a type of plant - the 1960s-era General Electric Mark 1 - that has been known since 1972 to be flawed and vulnerable to this type of disaster, and it has just been exposed to the fifth-largest earthquake in recorded history.
It shows us that nuclear plants must be better regulated and such cheap designs avoided or decommissioned, but it is hardly a condemnation of the technology. If the earthquake had burst a major dam - an event that would have killed thousands more people immediately - would the world have suddenly turned against hydroelectric generation?
More importantly, though, the Japanese moment represents a global choice, a fulcrum point in history.
We are being assaulted from three sides. First by nature, raw and unfettered, humanity's oldest and most constant enemy.
Second by our technology, gone terribly wrong and used carelessly - second only to nature as a threat to our being, as the words Auschwitz and Hiroshima ought to remind us constantly.
And third, by nature again, this time altered and distorted by our presence - an atmosphere too dense with our particles and gasses, requiring action to render it less of a threat.
That great Lisbon earthquake in 1755 taught us all a crucial lesson: We are alone in the world, without a beneficent God to protect us. Nature is not our gift from heaven but both our source of sustenance and our most pressing antagonist, and we must use our guile and devices to make nature work with us, not against us.
The 2011 earthquake repeats that lesson, but gives us a further choice: Can we prevent both nature and human inventions from harming us terribly, while using the latter to correct the distortions in the former?
We face the dual threat of nature rendering our technologies deadly and unworkable (nuclear disaster) or our technologies rendering nature menacing and hostile (climate change). The challenge of this age is to use these forces to correct the worst of each other.
It is a drama being played out in horrific microcosm on the Pacific coast of Japan this week. And it will soon be played out on a far larger stage.