The Planning of Pearl Harbor

Keystone/Getty Images
Keystone/Getty Images

On this date in 1941, the Imperial Japanese Navy launched an incredibly daring, technically sophisticated combined naval-aerial surprise attack on the U.S. naval base at Pearl Harbor, just northwest of Honolulu on the Hawaiian island of Oahu. The devastating aerial attack carried out by Japanese fighters, dive-bombers and torpedo planes crippled the U.S. Pacific fleet as a preamble to Imperial Japan’s lunge for strategic territories spanning the Pacific Ocean – but it also stirred the wrath of the American people, decisively ending U.S. isolationism and bringing the world’s largest industrial power squarely into the war against Japan and its European allies in Nazi Germany and Fascist Italy.

The Economic Vise

Pearl Harbor was born of strategic desperation. Over the previous couple years, Japan and the U.S. had been engaged in a tit-for-tat diplomatic and economic struggle, as the Roosevelt administration tried to restrain escalating Japanese aggression with embargoes on raw materials crucial for the Japanese war machine. Japan was heavily dependent on American supplies of oil and metal, with American shipments accounting for 80% of Japan’s oil and copper imports and almost half of its scrap iron imports.

Over several years the U.S. tightened the economic vise, responding to Japanese aggression in China and Southeast Asia by cutting off supplies of aircraft materials in 1939, scrap steel in 1940, and machine tools and metal ore in 1941. The final blow came with the suspension of oil deliveries in summer 1941.

At first, the Japanese hoped to negotiate their way out of the American economic embargo, but the Americans’ unwavering opposition to Japanese foreign policy convinced the Japanese leadership that further negotiation would be fruitless. They decided instead to deliver a knockout blow to the U.S. Pacific fleet with a surprise attack on Pearl Harbor, which would, they calculated, give Japan two years of unchallenged supremacy in the Pacific and a window in which they could conquer the oil-rich Dutch East Indies (today Indonesia) and the rubber plantations of Malaya. This, in turn, would give Japan enough resources to fight on once the U.S. rebuilt its Pacific fleet.

The odds were steep, to say the least. The plan required bringing a huge aircraft carrier battle fleet – comprised of six carriers, two battleships, and 48 combat and support vessels including cruisers, destroyers, submarines and tankers – 4,000 miles from the northeast coast of Japan to Pacific waters north of Hawaii in complete radio silence, a feat akin to smuggling an elephant through airport security. Ships in the attack fleet couldn’t communicate with home base, meaning there was no way to call off the attack without exposing their position.

Uphill Battle

In fact, the man in charge of planning the attack – the brilliant admiral Isoroku Yamamato, who had studied in the U.S. and respected American fighting spirit – advised against it, noting that even if it succeeded, Japan would still face an implacable enemy drawing on huge resources. He famously warned:

“Should hostilities once break out between Japan and the United States, it would not be enough that we take Guam and the Philippines, nor even Hawaii and San Francisco. To make victory certain, we would have to march into Washington and dictate the terms of peace in the White House. I wonder if our politicians (who speak so lightly of a Japanese-American war) have confidence as to the final outcome and are prepared to make the necessary sacrifices.”

But the hyper-nationalists in charge of Japan could not imagine submitting to what they perceived as American bullying, and decided on war, no matter how desperate, and no matter how steep the price. The die was cast.

After leaving Japan on November 26, the Japanese fleet steamed east across the Pacific, reaching a point about a thousand miles north of Hawaii on December 3. During their silent run, the Japanese ships were scattered by a sudden Pacific storm that lasted two days, stringing them out over hundreds miles of open water – but still managed to regroup with minimal use of short-range, low-power radio to communicate their positions, a remarkable feat of seamanship and navigation. Then from December 4-6, the fleet headed south until it reached a staging point a few hundred miles north of Oahu in the early morning hours of December 7.

Here the attack shifted from its naval phase to the aerial phase, with two waves of dive-bombers, fighters, and torpedo planes taking off from the carriers beginning at 6:10 a.m. Hawaii time. The first bombs fell at 7:48 a.m. Surprise was complete, as the operators of the primitive American radar mistook the approaching Japanese planes for a returning flight of U.S. B-17s.

Assisted by some ineffectual midget submarines, over two hours and 20 minutes 354 Japanese planes sank four American battleships, damaged three more and caused the last to run aground, while damaging or destroying ten other ships and over three hundred aircraft. The human toll came to 2,402 killed and 1,247 wounded, including 1,177 dead aboard the U.S.S. Arizona, the hardest-hit. Japanese losses were light, reflecting their success in achieving total surprise. Meanwhile Japanese forces fanned out across the Pacific, with near-simultaneous attacks on American forces in the Philippines and Guam, and tiny colonial garrisons in the Dutch East Indies and Malaya.

Although the attack was devastatingly successful, it was not the knockout blow Japanese planners had intended. Most importantly, the U.S. Navy’s Pacific carrier fleet was left untouched, since all three aircraft carriers were at sea during the attack. These would provide a crucial counterbalance to Japanese naval power in the Pacific in 1942, beginning with the stunning American victory at the battle of Midway.

Worse, the Japanese leadership badly miscalculated in their long-term strategy. In particular, they were over-optimistic about their ability to secure the long maritime supply lines from the oil wells of the East Indies to Japan; these proved vulnerable to American submarines, which helped strangle the Japanese economy in the final years of the war.

Last but not least, the effect on American morale was essentially the opposite of what the Japanese hoped. In the weeks following Pearl Harbor (which included Adolf Hitler’s declaration of war on the U.S. on December 11), approximately one million American men volunteered for military duty. This would be followed by a draft that eventually built the American military into 12-million-strong juggernaut by 1944, compared with Japan’s 4.3 million men in military service by the end of the war.

This post originally appeared in 2011.

10 of the Best Indoor and Outdoor Heaters on Amazon

Mr. Heater/Amazon
Mr. Heater/Amazon

With the colder months just around the corner, you might want to start thinking about investing in an indoor or outdoor heater. Indoor heaters not only provide a boost of heat for drafty spaces, but they can also be a money-saver, allowing you to actively control the heat based on the rooms you’re using. Outdoor heaters, meanwhile, can help you take advantage of cold-weather activities like camping or tailgating without having to call it quits because your extremities have gone numb. Check out this list of some of Amazon’s highest-rated indoor and outdoor heaters so you can spend less time shivering this winter and more time enjoying what the season has to offer.

Indoor Heaters

1. Lasko Ceramic Portable Heater; $20

Lasko/Amazon

This 1500-watt heater from Lasko may only be nine inches tall, but it can heat up to 300 square feet of space. With 11 temperature settings and three quiet settings—for high heat, low heat, and fan only—it’s a dynamic powerhouse that’ll keep you toasty all season long.

Buy it: Amazon

2. Alrocket Oscillating Space Heater; $25

Alrocket/Amazon

Alrocket’s oscillating space heater is an excellent addition to any desk or nightstand. Using energy-saving ceramic technology, this heater is made of fire-resistant material, and its special “tip-over” safety feature forces it to turn off if it falls over (making it a reliable choice for homes with kids or pets). It’s extremely quiet, too—at only 45 dB, it’s just a touch louder than a whisper. According to one reviewer, this an ideal option for a “very quiet but powerful” heater.

Buy it: Amazon

3. De’Longhi Oil-Filled Radiator Space Heather; $79

De’Longhi/Amazon

If you prefer a space heater with a more old-fashioned vibe, this radiator heater from De’Longhi gives you 2020 technology with a vintage feel. De’Longhi’s heater automatically turns itself on when the temperatures drops below 44°F, and it will also automatically turn itself off if it starts to overheat. Another smart safety feature? The oil system is permanently sealed, so you won’t have to worry about accidental spills.

Buy it: Amazon

4. Aikoper Ceramic Tower Heater; $70

Aikoper/Amazon

Whether your room needs a little extra warmth or its own heat source, Aikoper’s incredibly precise space heater has got you covered. With a range of 40-95°F, it adjusts by one-degree intervals, giving you the specific level of heat you want. It also has an option for running on an eight-hour timer, ensuring that it will only run when you need it.

Buy it: Amazon

5. Isiler Space Heater; $37

Isiler/Amazon

For a space heater that adds a fun pop of color to any room, check out this yellow unit from Isiler. Made from fire-resistant ceramic, Isiler’s heater can start warming up a space within seconds. It’s positioned on a triangular stand that creates an optimal angle for hot air to start circulating, rendering it so effective that, as one reviewer put it, “This heater needs to say ‘mighty’ in its description.”

Buy it: Amazon

Outdoor Heaters

6. Mr. Heater Portable Buddy; $104

Mr. Heater/Amazon

Make outdoor activities like camping and grilling last longer with Mr. Heater’s indoor/outdoor portable heater. This heater can connect to a propane tank or to a disposable cylinder, allowing you to keep it in one place or take it on the go. With such a versatile range of uses, this heater will—true to its name—become your best buddy when the temperature starts to drop.

Buy it: Amazon

7. Hiland Pyramid Patio Propane Heater; Various

Hiland/Amazon

The cold’s got nothing on this powerful outdoor heater. Hiland’s patio heater has a whopping 40,000 BTU output, which runs for eight to 10 hours on high heat. Simply open the heater’s bottom door to insert a propane tank, power it on, and sit back to let it warm up your backyard. The bright, contained flame from the propane doubles as an outdoor light.

Buy it: Amazon

8. Solo Stove Bonfire Pit; $345

Solo Stove/Amazon

This one is a slight cheat since it’s a bonfire pit and not a traditional outdoor heater, but the Solo Stove has a 4.7-star rating on Amazon for a reason. Everything about this portable fire pit is meticulously crafted to maximize airflow while it's lit, from its double-wall construction to its bottom air vents. These features all work together to help the logs burn more completely while emitting far less smoke than other pits. It’s the best choice for anyone who wants both warmth and ambiance on their patio.

Buy it: Amazon

9. Dr. Infrared Garage Shop Heater; $119

Dr. Infrared/Amazon

You’ll be able to use your garage or basement workshop all season long with this durable heater from Dr. Infrared. It’s unique in that it includes a built-in fan to keep warm air flowing—something that’s especially handy if you need to work without wearing gloves. The fan is overlaid with heat and finger-protectant grills, keeping you safe while it’s powered on.

Buy it: Amazon

10. Mr. Heater 540 Degree Tank Top; $86

Mr. Heater/Amazon

Mr. Heater’s clever propane tank top automatically connects to its fuel source, saving you from having to bring any extra attachments with you on the road. With three heat settings that can get up to 45,000 BTU, the top can rotate 360 degrees to give you the perfect angle of heat you need to stay cozy. According to a reviewer, for a no-fuss outdoor heater, “This baby is super easy to light, comes fully assembled … and man, does it put out the heat.”

Buy it: Amazon

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A Brief History of Mashed Potatoes

mphillips007/iStock via Getty Images Plus
mphillips007/iStock via Getty Images Plus

During the Seven Years War of the mid-1700s, a French army pharmacist named Antoine-Augustin Parmentier was captured by Prussian soldiers. As a prisoner of war, he was forced to live on rations of potatoes. In mid-18th century France, this would practically qualify as cruel and unusual punishment: potatoes were thought of as feed for livestock, and they were believed to cause leprosy in humans. The fear was so widespread that the French passed a law against them in 1748.

But as Parmentier discovered in prison, potatoes weren’t deadly. In fact, they were pretty tasty. Following his release at the end of the war, the pharmacist began to proselytize to his countrymen about the wonders of the tuber. One way he did this was by demonstrating all the delicious ways it could be served, including mashed. By 1772, France had lifted its potato ban. Centuries later, you can order mashed potatoes in dozens of countries, in restaurants ranging from fast food to fine dining.

The story of mashed potatoes takes 10,000 years and traverses the mountains of Peru and the Irish countryside; it features cameos from Thomas Jefferson and a food scientist who helped invent a ubiquitous snack food. Before we get to them, though, let’s go back to the beginning.

The Origins of the Potato

Potatoes aren’t native to Ireland—or anywhere in Europe, for that matter. They were most likely domesticated in the Andes mountains of Peru and northwest Bolivia, where they were being used for food at least as far back as 8000 BCE.

These early potatoes were very different from the potatoes we know today. They came in a variety of shapes and sizes and had a bitter taste that no amount of cooking could get rid of. They were also slightly poisonous. To combat this toxicity, wild relatives of the llama would lick clay before eating them. The toxins in the potatoes would stick to the clay particles, allowing the animals to consume them safely. People in the Andes noticed this and started dunking their potatoes in a mixture of clay and water—not the most appetizing gravy, perhaps, but an ingenious solution to their potato problem. Even today, when selective breeding has made most potato varieties safe to eat, some poisonous varieties can still be bought in Andean markets, where they're sold alongside digestion-aiding clay dust.

By the time Spanish explorers brought the first potatoes to Europe from South America in the 16th century, they had been bred into a fully edible plant. It took them a while to catch on overseas, though. By some accounts, European farmers were suspicious of plants that weren’t mentioned in the Bible; others say it was the fact that potatoes grow from tubers, rather than seeds.

Modern potato historians debate these points, though. Cabbage’s omission from the Bible didn’t seem to hurt its popularity, and tulip cultivation, using bulbs instead of seeds, was happening at the same time. It may have just been a horticultural problem. The South American climates potatoes thrived in were unlike those found in Europe, especially in terms of hours of daylight in a day. In Europe, potatoes grew leaves and flowers, which botanists readily studied, but the tubers they produced remained small even after months of growing. This particular problem began to be remedied when the Spanish started growing potatoes on the Canary Islands, which functioned as a sort of middle ground between equatorial South America and more northerly European climes.

It’s worth pointing out, though, that there is some evidence for the cultural concerns mentioned earlier. There are clear references to people in the Scottish Highlands disliking that potatoes weren’t mentioned in the Bible, and customs like planting potatoes on Good Friday and sometimes sprinkling them with holy water suggest some kind of fraught relationship to potato consumption. They were becoming increasingly common, but not without controversy. As time went on, concerns about potatoes causing leprosy severely damaged their reputation.

Early Mashed Potato Recipes

A handful of potato advocates, including Parmentier, were able to turn the potato's image around. In her 18th-century recipe book The Art of Cookery, English author Hannah Glasse instructed readers to boil potatoes, peel them, put them into a saucepan, and mash them well with milk, butter, and a little salt. In the United States, Mary Randolph published a recipe for mashed potatoes in her book, The Virginia Housewife, that called for half an ounce of butter and a tablespoon of milk for a pound of potatoes.

But no country embraced the potato like Ireland. The hardy, nutrient-dense food seemed tailor-made for the island’s harsh winters. And wars between England and Ireland likely accelerated its adaptation there; since the important part grows underground, it had a better chance of surviving military activity. Irish people also liked their potatoes mashed, often with cabbage or kale in a dish known as colcannon. Potatoes were more than just a staple food there; they became part of the Irish identity.

But the miracle crop came with a major flaw: It’s susceptible to disease, particularly potato late blight, or Phytophtora infestans. When the microorganism invaded Ireland in the 1840s, farmers lost their livelihoods and many families lost their primary food source. The Irish Potato Famine killed a million people, or an eighth of the country’s population. The British government, for its part, offered little support to its Irish subjects.

One unexpected legacy of the Potato Famine was an explosion in agricultural science. Charles Darwin became intrigued by the problem of potato blight on a humanitarian and scientific level; he even personally funded a potato breeding program in Ireland. His was just one of many endeavors. Using potatoes that had survived the blight and new South American stock, European agriculturists were eventually able to breed healthy, resilient potato strains and rebuild the crop’s numbers. This development spurred more research into plant genetics, and was part of a broader scientific movement that included Gregor Mendel’s groundbreaking work with garden peas.

Tools of the Mashed Potato Trade

Around the beginning of the 20th century, a tool called a ricer started appearing in home kitchens. It’s a metal contraption that resembles an oversized garlic press, and it has nothing to do with making rice. When cooked potatoes get squeezed through the tiny holes in the bottom of the press, they’re transformed into fine, rice-sized pieces.

The process is a lot less cumbersome than using an old-fashioned masher, and it yields more appetizing results. Mashing your potatoes into oblivion releases gelatinized starches from the plant cells that glom together to form a paste-like consistency. If you’ve ever tasted “gluey” mashed potatoes, over-mashing was likely the culprit. With a ricer, you don’t need to abuse your potatoes to get a smooth, lump-free texture. Some purists argue that mashed potatoes made this way aren’t really mashed at all—they’re riced—but let's not let pedantry get in the way of delicious carbohydrates.

The Evolution of Instant Mashed Potatoes

If mashed potato pedants have opinions about ricers, they’ll definitely have something to say about this next development. In the 1950s, researchers at what is today called the Eastern Regional Research Center, a United States Department of Agriculture facility outside of Philadelphia, developed a new method for dehydrating potatoes that led to potato flakes that could be quickly rehydrated at home. Soon after, modern instant mashed potatoes were born.

It’s worth pointing out that this was far from the first time potatoes had been dehydrated. Dating back to at least the time of the Incas, chuño is essentially a freeze-dried potato created through a combination of manual labor and environmental conditions. The Incas gave it to soldiers and used it to guard against crop shortages.

Experiments with industrial drying were gearing up in the late 1700s, with one 1802 letter to Thomas Jefferson discussing a new invention where you grated the potato and pressed all the juices out, and the resulting cake could be kept for years. When rehydrated it was “like mashed potatoes” according to the letter. Sadly, the potatoes had a tendency to turn into purple, astringent-tasting cakes.

Interest in instant mashed potatoes resumed during the Second World War period, but those versions were a soggy mush or took forever. It wasn’t until the ERRC’s innovations in the 1950s that a palatable dried mashed potato could be produced. One of the key developments was finding a way to dry the cooked potatoes much faster, minimizing the amount of cell rupture and therefore the pastiness of the end-product. These potato flakes fit perfectly into the rise of so-called convenience foods at the time, and helped potato consumption rebound in the 1960s after a decline in prior years.

Instant mashed potatoes are a marvel of food science, but they’re not the only use scientists found for these new potato flakes. Miles Willard, one of the ERRC researchers, went on to work in the private sector, where his work helped contribute to new types of snacks using reconstituted potato flakes—including Pringles.