The past week’s 20-point drop in the market price of oil is primarily attributable to forceful declarations by key Democrats in Congress, including Sen. Jim Webb of Virginia, that they’ll investigate the role of dubious speculation in driving the price to its recent peak of $147 a barrel.

Hedge funds and others working on the margins of speculation do not like to operate in sunlight. Like cockroaches scurrying when uncovered beneath a household appliance, the speculators have begun ducking for cover.

If you are looking for a correlation to explain the sudden drop in oil, you can find it there.

But the oil price can drop only so much before the reality of supply and demand becomes the dominant operating principle, and despite drops in demand due to high costs and other economic factors, it is the lack of the ability of the supply to meet the demand that remains the stubborn, intractable reality of our time.

It is slowing growth globally and there is no remedy on the horizon. That is why, apart from our grinning U.S. president, there are simply no Pollyanna forecasters to be found these days, in case you haven’t noticed. There are only varying degrees of doom and gloom.

Last Sunday, both the New York Times and Washington Post devoted a big part of their front pages to the next phase of the careening economic downturn, looking beyond the mortgage crisis to the personal debt crisis.

This is the next shoe that is about to drop.

Defaults on personal credit cards are already hitting banks and credit card companies hard, and those, such as American Express, without strong deposit or retail components are teetering on the precipice.

The Times’ full-page graphic on Sunday told a grim story of the timeline since the 1920s, showing a systemic increase in the average American household debt burden, especially since the 1980s.

The average household debt is now $117,951. This breaks down to an average credit card debt of $8,565, vehicle and tuition loan debt of $14,414, home equity loan debt of $10,062 and mortgage debt of $84,911.

On the equity side, the average household annual savings is a paltry $392, the lowest level since the Great Depression, and the lowest in comparison to debt ever.

These are the averages, meaning it’s even worse than this for fully half of American households, to lesser or greater degrees.

On top of this come the specters of inflation, growth in unemployment, tax hikes to fund local governments struggling under similar burdens, and greater restrictions on access to credit. The latter is a result of the mortgage meltdown and rising levels of defaults on personal debt, including a 30 percent increase in the rate of personal bankruptcies this spring.

These factors are already translating into a dramatic slowdown in discretionary spending, ranging from fewer and shorter vacations to restrained spending in retail stores, restaurants and on entertainment.

Big ticket prices for touring performers and sporting teams are becoming affordable only to the super-wealthy, leaving the rest of us to spend more time watching TV, instead.

Many Americans are already finding it is not that painful to reduce their spending to a considerable degree, and while that is hurting the overall economy, including the ability of the Chinese to export consumer goods to the U.S., it barely begins to address the problems associated with the accumulated personal debt that is currently hanging over so many.

All of these factors contribute to a snowball effect, and for some observers, these trends have occurred periodically as part of “business cycles.”

However, the trend line in the New York Times graphic on Sunday is hardly cyclical in appearance. The differential between household debt and equity has grown steadily since the 1920s, and ridiculously in the last 20 years.

On top of that, the decline in the rate of supply of oil is not cyclical, either. Once the resource supply is fundamentally past its peak, the ability to extract oil becomes more and more difficult and costly. It simply won’t bounce back.