There's a lot to worry about in this modern world of ours: terrorism, environmental catastrophe, the possibility that a giant meteorite might smack into Earth, knocking us forever into the freezing void of space. So let me as a public service suggest one item you can safely remove from your list: that record-breaking U.S. current-account deficit--of which the trade deficit is the best known component--that has business writers from here to Shanghai hitting their exclamation keys.

The business pages are filled with scary figures: The United States is spending US$1.8-billion more per day than it earns! The deficit is twice as big as it was in the 1980s! It's hit 5.7% of gross domestic product, an all-time record! This cannot go on forever!

It is a perverse fact of financial journalism that the profession admires and rewards its pessimists and hysterics. And nothing makes the pessimists and hysterics quiver quite like a current account deficit.

The current account tracks the amount of money a country earns from all sources and the amount it spends. It is a statistic that plays on the imagination because it seems to resemble the kind of household accounting we all do. If our families spend more than they earn, we are in trouble--and it just seems obvious that the same must be true for a country as a whole.

If there is one lesson that John Maynard Keynes ought to have pounded into the heads of every amateur economist, however, it is that countries are not households. Countries can spend more than they earn: The United States did so for almost all of the century-plus from 1790 until 1914; Canada has done done so for almost all its record history.

How is this possible?

The key is that word "spending." When a household spends, it spends mostly on personal consumption: clothes, cars, etc. But much of a country's spending is investment: new factories, new power plants, new fibre optic networks and so on.

And if a country is an attractive place to do business, not all its would-be investors are going to be locals. When foreigners put money into a country, they increase its "spending" even though earnings in that country have not increased at all. In other words, every time somebody in Russia, France or Japan buys a share of Microsoft, he or she causes the U.S. current account deficit to go up.

Is that bad news for the United States? Hardly. In fact, the eagerness of non-Americans to purchase U.S. assets over the past three years underscores a problem that--unlike the current account deficit--actually is worth worrying about: The fact that people in Russia, France, and Japan see so few investment opportunities in their own countries that they would prefer to put their money into something, anything, located in the relatively fast growing United States.

The current deficit is often presented as if it were some kind of moral indicator: The lower, the more virtuously frugal. But right now, the United States is spending a great deal overseas because the price of oil has risen high; foreigners are buying relatively little in the United States because the European and Japanese economies are so sluggish; and foreign investment is surging into the country for lack of better global alternatives.

The American current account deficit, in other words, is an indicator of the strength and vitality of the U.S. economy. The only thing scary about the statistic is what it reveals about the weakness and fragility of the other major world economies, especially those of Europe.

The witty American economist Herbert Stein once quipped, "If something cannot go on forever, it will stop." A trade deficit of 5.7% of U.S. GDP probably cannot go on forever, and so it will stop, just as the trade deficits of the 1980s stopped. Either the U.S. economy will slow down and import less; or the price of oil will drop and imports will cost less; or the European and Japanese economies will revive and import more; or something will happen to make investment in Europe and Japan less unattractive than it is today.

If the world is lucky, those changes will come gradually and smoothly. Or they could arrive with a vicious shock, as they did at the end of the 1990s, when the U.S. stock market and the whole Japanese economy crashed at the same time.

A U.S. recession, for example, would cut the current account deficit. So would a sudden rise in U.S. interest rates. So would a sharp rise in the U.S. dollar. These are all cures far worse than the alleged problem.

If you must worry, worry about the Japanese slowdown or European unemployment or the high price of oil. But for the U.S. current account deficit, probably the best advice to follow is that which my old boss Bob Bartley of the Wall Street Journal used to offer, before his untimely death: "Stop collecting that damn statistic."

David Frum is a resident fellow at AEI.