I used to be picky about beer. When I pulled a can or bottle out of a six-pack, I'd go right ahead and drink the whole thing. After all, I used to think, beer's no good after it's been opened. Who wants a can that's sat overnight in the fridge?

Then I came to Japan. Last night, as I stood in front of the refrigerator and extracted the half-full bottle I had lovingly stoppered the night before, I thought about how my outlook had changed. The cheapest, most standard-issue biere ordinaire I have been able to find in Tokyo comes to almost $1.50 per bottle, $9 a six-pack, $36 a case. That might not sound surprising or traumatic as an isolated instance -- in fancy American bars, a beer would cost more. But since, far from being isolated, it's in line with the price of everything else in Japan, it has radically altered my family's notions of affluence, frugality and what we can afford to consume.

The background to our struggle, of course, is the sickening increase in the value of the yen. A year ago, when we decided to come to Japan, the dollar was worth 240 yen. Two months ago, when we arrived, it was above 180. Later it crashed below 160, and after a modest "recovery" it's been bouncing around in the 160s.

A few days after our arrival, we contemptuously turned down a department-store manager who offered to accept our traveler's checks at 174 yen to the dollar. What did he take us for, suckers and rubes? Now, if we were ever to see 174 posted in a bank's window (we check the rates no more than 10 to 15 times a day) we'd rush right in and convert every penny we owned.

The mighty yen and pathetically weak dollar are presumably good for American exporters. But they are bad for particular Americans -- for instance, us. My family is willing to do our national service, if this is the form it takes. But we're turning into monsters as we serve.

A few evenings ago, I watched my nine-year-old son take a big red apple from the fruit basket and slice it in half with his cub scout knife. It was a scene fit for Frank Capra, or Norman Rockwell: a bright-eyed boy, a healthful snack, loving parents (and semi-loving brother) looking on with joy. But I had thoughts worthy only of Ebeneezer Scrooge. As my son innocently circled back toward the remaining half in the fruit basket, I asked myself with dread, is he going to eat the whole thing? At the corner grocery, this one apple had cost nearly $2, and because of the nose-diving dollar, the next one was sure to cost more.

My wife and I shoot suspicious glances at each other as the coffee pot gets down to its last meager cup. Who will drink it? Do we really need to make another pot today? My boys love to drink milk, and I have always loved to watch them, imagining it building their bones even as I look on. It is still a heartwarming picture, but now a costly one as well, since each gallon of milk costs $5.

The boys will have to do without the strong muscles -- and my wife and I without the clogged-up arteries -- that come with eating meat. On our last walk past the butcher's, the asking price for a pound of beef was $45.

I have averted my thoughts altogether from such delicacies as wine.

I know that a list of prices gets very boring, if you're not paying them yourself. But indulge me a moment more. Local phone calls are cheap here (one of four bargains: the others are subway tickets, onions and, incongruously enough, fresh-baked and delicious french bread). But having a home telephone installed costs almost $500. Going to the movies is $9 a head.

As far as I can tell from prowling through the electronics stores, everything that's made in Japan costs more to buy in Japan than in the U.S. Since the Japanese believe in fair trade, everything that comes from the U.S. costs more, too.

Sushi bars may be more authentic here than in America, and the sushi men more colorful in their decorated hachi-maki (the inspirational headbands so familiar from kamikaze movies), but most of the tuna is flown in fresh from Boston, and the airfreight shows in the price. Newspapers have recently pointed out that, while the yen is going up, prices of imported goods have barely come down -- except for California lemons, which are 60 percent cheaper than a year ago. If we could live on lemons we would not be so obsessed with the price of everything else.

No one could have been surprised when an international business organization recently rated Tokyo the most expensive city in the world. But I was amazed to read that the calculations did not include housing -- which is like estimating annual air-conditioning costs without counting July and August. The house we left behind in Northwest Washington is so enormous that, if it were in Japan, it would be a shrine and its yard a national forest. We rented it out for a little more money than we're spending here for a two-bedroom apartment an hour's commute from downtown. By local standards our apartment is a real find -- clean, cheery, with friendly landlords. Still, we have to turn our shoulders sideways to walk down the hall. We live in dread of our next utility bill, since electricity costs three times as much per kilowatt as the American average.

Fifteen years ago, just after we were married, my wife and I found ourselves in a similar bind. Full of youthful idealism, and sick of shivering year-round in England, we joined a work gang in west Africa, building schools in the bush. A few days after we arrived, Richard Nixon took America off the gold standard, and for the next month or two, the local authorities found it inconvenient to exchange us dollars for cedis and pesewas.

We had about $200 in local currency to nurse through two months. I remember thinking, "If we eat that pineapple tonight, what will we eat tomorrow?" We once met hunters who'd caught a dog-sized, rat-like rodent called a "grasscutter." We made a deal for its haunches, at a good price, and were happy for days. A year later we were still so chastened by the experience that I leapt at a job with the Washington Monthly at $8,400 a year, not simply for the challenge but also because of the good pay.

In some ways, being in Japan is very much the same. Our children have learned not to leave anything, ever, uneaten on their platters. (Little did they suspect that the "hungry children in Asia" would turn out to be them.)

In fact, we sometimes think they have taken their new role as depression babies a little too much to heart. As we walk around town they constantly scramble under vending machines and rummage through pay telephones, in hopes of finding a few yen. When we took them to the ancient, holy, unbombed city of Nara, they spared barely a glance at the world's largest bronze statue, a mysterious brooding Buddha. They had trapped a group of Japanese students in one corner of the temple and were trading American quarters for 100-yen coins, which are worth 60 cents. "Rats!" they said (we are a genteel family) on the train back home. "Why didn't we bring more change?"

My wife and I are no less warped. When I go on expense-account lunches, I eat all the bread out of the basket and order the biggest dessert. We pause in terror at the dinner table, chopsticks frozen halfway to our mouths, when we hear shortwave radio reports about James Baker's tireless efforts to talk the dollar down. (Hey, big guy, take a break.)

But there is an ominous way in which this experience differs from our African adventure, and from anything else Americans have seen in the last 40 years. In Africa we were temporarily inconvenienced by an accident of timing. What's going on in Japan is no accident, and unfortunately not temporary. The U.S. is finally paying the price for losing the ability to compete. We're seeing it more vividly than most people, since we have no choice but to buy Japanese. But the same verdict is being rendered on all Americans: We haven't been earning our keep.

The Japanese have a favorite explanation for the huge trade surpluses they have piled up (which, of course, are finally pushing the dollar down). They talk not of trade barriers, which certainly exist, nor of American military spending, which diverts our engineers into making missiles while theirs are designing chips and VCRs. Instead they talk about "fighting spirit," roughly translated as a sense of do-or-die. They have fighting spirit, and so they never stop trying. They think our national slogan has instead become "Miller Time."

I know this is too one-sided and simple a view. Still, at its heart it's true. We glimpsed the unsettling side of "fighting spirit" late last month, on the emperor's 85th birthday.) As we stood in the courtyard before the imperial palace, we were surrounded by the usual throngs of Japanese waving flags and yelling "Banzai! Banzai!" I wished that Caspar Weinberger, and anybody else who is pushing the Japanese to rearm, had been standing in the crowd that day. (My boys were yelling "Banzai!" too. Perhaps they thought that, by ingratiating themselves, they could get the family's income converted from dollars to yen.) The rest of the year, the Japanese are not bowing to theemperor, but they are demonstrating loyalty to a larger cause through hard work.

In ways too familiar to bear repetition, the Japanese display their determination to save, produce, prevail. They are motivated by many forces, from government policy to the memories of deprivation after the war; but all the reasons boil down to the feeling that the world doesn't owe them a living, that they have to earn it themselves.

My parents' generation had that feeling, because of what they'd been through in the Depression. My children may well develop it, because of what they're going through right now. But my generation, raised in affluence in the 1950s and 1960s, never needed to develop "fighting spirit" of this particular sort, and the country as a whole seems to have shucked it off. Each day I'm here, I find it more incredible and obscene that in the last five years Americans could have borrowed so much money -- mainly, of course, from Japan -- to build bombers and disburse pensions without the nuisance of paying more tax.

Some day we will have to pay -- as a net international debtor paying interest overseas, we're starting already. If you want to get a hint of what the full reckoning will be like, come join us in Japan.