The first is the nonglobal nature of globalization. Far from being perfectly integrated, the world's markets for goods, capital and labor appear to have become remarkably segmented. Thus, the overwhelming bulk of American, Canadian and Mexican trade now takes place within the North American Free Trade Area, just as most European trade takes place within Europe. Back in 1913, international capital was truly international: about 63 percent of foreign direct investment in 1913 went to developing countries. But in 1996, the proportion was just 28 percent. Labor mobility is also distorted, with the United States able to cherry-pick the best-qualified and most-talented workers from European and Asian economies under its various visa programs while letting in many more unskilled (and untaxed) Latino workers through the Mexican back door.

This is one key reason that the process we call globalization has tended to result in widening inequality between nations. In the 1960's, the richest fifth of the world's population had a total income 30 times as great as the poorest fifth's; in 1998, the ratio was 74:1. In 1965, real gross domestic product per capita in Chad was one-fifteenth of the U.S.'s ; in 1990, one-fiftieth. If there was a substantial measure of convergence of incomes during the first age of globalization, in this age there is a pronounced divergence. And such inequality seems likely to increase the resentment felt in poorer countries toward the super-rich United States. (That said, we should not make the mistake of assuming that this poverty is the principal cause of support for organizations like Al Qaeda, most of whose recruits come from relatively prosperous backgrounds.)

Even more worrying is the medium-term outlook for global energy supplies. The rise of the S.U.V. as a status symbol shows how complacent Americans are about their supply of oil and petroleum. They should not be. True, oil prices are low right now: a barrel of West Texas crude sells for about $20, less than half the price (in real terms) as at the peak of the oil crisis in 1982. But what made prices go through the roof in the 1970's and early 1980's was political instability in the Middle East: the anti-Israel Arab oil embargo, the Iranian revolution and the Iran-Iraq war. It's no great stretch to imagine something similar happening again. (Even the demand-side shock of the recent U.S. boom trebled the oil price between December 1998 and October 2000's $33 peak.)

The realities are stark. The Middle East accounts for 31 percent of world oil production but just 6 percent of consumption. North America accounts for about 18 percent of world oil production but consumes 30 percent. Even more sobering, however, are the figures for world oil reserves: North America has just 6 percent of them; the Middle East 65 percent.

Feeling comfortable? Total U.S. energy consumption -- of which petroleum accounts for about two-fifths -- has risen about 27 percent since 1972, while oil reserves have fallen by about 30 percent. Right now, the United States depends on the Persian Gulf -- mainly Saudi Arabia -- for about 12 percent of its oil imports, but that figure is bound to rise as OPEC countries account for an ever-increasing share of the world's available oil.

The time frame may be much tighter than S.U.V. manufacturers realize. Kenneth S. Deffeyes of Princeton University predicts that global oil production will start to decline from 2004. At a conference at the Royal United Services Institute in London in October, experts warned that from 2008 supplies of non-OPEC oil will fall steeply -- reaching close to zero in 2040 -- and that, barring some major technological breakthroughs, there will be an effective world shortage from 2010.

Yet even that estimate could prove to be overoptimistic if there is a regime change in Saudi Arabia. Like ''the coming oil crisis,'' the fall of the Saudi monarchy has been prophesied so often that many people have stopped believing it could ever happen. Don't be so sure. The position of the ruling dynasty increasingly resembles that of the shah of Iran in the late 1970's. Low oil prices may have been good for the West, but they have produced a significant fall in per capita income in Saudi Arabia, creating a reserve army of disenchanted young men who are the natural recruits of Al Qaeda.