For years, Bernie Madoff, all-around nice guy, pulled billions of dollars of foreign and domestic money into his investment fund. His lure? He promised the implausible combination of good returns and low risk -- and people believed him.

Painfully, the allegations of fraud surrounding the Madoff affair are also exposing the fundamental fallacy of the global economy. Like Madoff's trusting investors, the rest of the world was willing to assume that the U.S. economy as a whole was a low-risk, good-return investment. This belief drove the entire structure of global trade and finance for the past 10 years. And when the subprime crisis showed this assumption of low risk to be false, the financial crisis resulted.

Consider this: Since the Asian financial crisis of 1997-98, the rest of the world has been willing to lend money to finance the U.S.'s huge and growing trade deficit. Not just small amounts of cash either: over the past decade, the U.S. borrowed a cumulative total of $5 trillion from foreigners at relatively low interest rates.

Why were foreigners so generous?

Without this flow of easy money into the U.S., globalization in its current form would not have been possible. The U.S. was the consumer of last resort, absorbing cars from Germany and Japan, electronics from Taiwan and Korea, and clothes and furniture from China. The earth was flat, and why not? Pluck a laptop from Taiwan and pay for it with a home equity loan, which -- if you trace back the connections -- was at least partly funded with foreign money, too.

The big unanswered question, for years, was why this money flow persisted. Why the heck were foreign investors willing to lend the U.S. such large amounts of money on such good terms? Economists and journalists spun out hypothesis after hypothesis (we'll see more below), but there was no agreement on why.

Now we see what happened. Wall Street firms -- big operators like Lehman and relatively small fish like Madoff -- told foreign investors they could put their money into the U.S. -- the world's safest economy -- and still make decent returns. Madoff, of course, appears to have lied. He allegedly ran an investment scam that has resulted in billions of dollars of losses reported around the world, including $4 billion in Switzerland and $3 billion in Spain.

Exporting 'low risk' Derivatives

But it wasn't simply Madoff. The Wall Street boom of recent years was built, as far as I can figure out, on selling the low-risk story to foreign investors. In fact, most of the financial innovations of recent years were about making investments in the U.S. 'safer' for foreign investors. The enormous growth of foreign exchange derivatives enabled those abroad to protect their U.S. investments from exchange-rate fluctuations.

The sudden increase in credit default swaps could be used to protect foreign bond investors from problems with individual countries. And collateralized debt obligations, which could be divided into high-risk and low-risk pieces, increased the supply of low-risk investments to be sold outside the U.S.

This low-risk, good-return story attracted investors from around the world. One example: Lehman sold $2 billion in 'mini-bonds' to Hong Kong investors, including many retirees.

However, the low-risk, good-return story simply wasn't true, for two key reasons: First, the U.S. economy was supposed to be on the cutting edge of innovation. Innovation through technological change, by nature, is a very risky activity. Sometimes it pays off and sometimes it doesn't. If the investment in innovation pays off, the economy booms, as it did during the second half of the 1990s.

U.S. Regulation Failed

But innovation has fallen short in recent years. Biotech and nanotech still have not come to fruition, and alternative energy is moving slowly. As a result, the U.S. economy has fallen short of expectations. The income isn't there, and the debt just piles up.

The second reason why the low-risk, good-return story wasn't true: the breakdown of regulation. And that's where we come back to the alleged Madoff scam. His was no complicated global securitization, based on black-box rocket science. Instead, it appears to be a good old-fashioned Ponzi scheme, enabled by a lack of government supervision.

What comes next? The fallacy is punctured. Globalization will be seen as what it is -- a game with risks that can't be wished away. And U.S. prosperity will depend on the success or failure of its ability to innovate -- not its ability to tell an implausible story to foreign investors.

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