One day, 20 or 30 years from now, we'll be able to look back on this time of economic crisis and say, "We remember when that happened."

For our grandparents, the seminal economic event of their lives was the stock market crash of 1929 and the Depression that followed. For our parents, the crucial economic memory wasn't of one single event, but instead the increasing prosperity and growth of the middle class that transformed America post-World War II.

And now, for those of us who came of age in the Baby Boom years, and for our children, there is our own historical moment, still being written. Over the last few months, starting with the collapse of investment bank Bear Sterns in March and culminating in the cataclysmic events of this past week on Wall Street, we have experienced a titanic shift in our sense of order, security and well-being.

Institutions -- banks, insurance companies, the federal giants Fannie Mae and Freddie Mac -- whose names were once synonymous with stability have been transformed into debt-hobbled beggars who need life-support. The retirement funds that held our savings have lost thousands of dollars every day. Our money-market accounts -- surely these were the safest of the safe! -- were likewise threatened, and the federal government moved in to shore up even their solvency.

What does it mean when banks are so afraid of the risks that they won't lend to each other, let alone to customers? What does it mean that the federal government is, right now, engineering the purchase of hundreds of billions of dollars in bad loans from financial institutions? What does it mean that all we seem to hear these days are the words "unthinkable," "risky" "bailout" and "unprecedented"?

It will take the hindsight of history to take the full measure of this difficult era's meaning. What we know now is that for many of us, it is a frightening time, when what we believed to be bedrock instead crumbled before our eyes.

We are not economists. We would not presume to prescribe solutions to the complex crisis we face. But there are some things we know. At the risk of sounding like one of those posters that tells you that all you really needed to know you learned in kindergarten, here are our bedrock principles that have not crumbled during this crisis:

* It's a bad idea to lend money to people who can't afford to pay it back. It's an especially bad idea to build an entire housing bubble on loans like this. And its a really awful idea to build an international economic system on such risky loans.

* It's not smart to insure loans made to people who can't afford to pay them back. AIG has now learned this. So have the taxpayers who are picking up the tab for AIG's losses.

* The diabolical geniuses on Wall Street will always find ways to make money that are risky and just this side of the law. Some of those methods should now be regulated out of existence. When they are, the diabolical geniuses will find new, and equally risky, ways to make money.

* It's really not fair to let businesses and their stockholders make a profit and then stick the taxpayers with the bill when those business generate massive losses.

* There is a role for the federal government in the financial markets. We'd prefer that the feds play the role of traffic cop before trouble starts, rather than acting as ambulance drivers after the crash happens.

There is one good aspect to the recent panic on Wall Street: It's clamped down on the trivial talk emanating from the presidential campaign trail. But it has also raised the stakes on that trail.

Whoever is inaugurated on Jan. 20 will face a much more challenging job than when he entered the race. The complexity of the economic problems facing this country -- and the world -- is enormous. We wish him the best of luck.