Somewhat predictably, stocks began their historically worst month on a down note. As Fool contributor John Maxfield discussed in detail earlier today, a combination of poor data on manufacturing activity and the ongoing European financial crisis helped raise fears about the prospects for the stock market. The Dow Jones Industrials (INDEX: ^DJI) lost as much as 110 points early in the session, but the market rallied late, and the Dow managed to cut its previous losses roughly in half.

But many Dow stocks weren't able to make back much of their lost ground. Caterpillar (NYSE: CAT) remained off about 3% as bears paid particular attention to the company's industrial focus. Judging from performance elsewhere in the sector, it appears that the mining element of its business was largely to blame for the drop, as rival Joy Global (NYSE: JOY) also had a similar drop while more construction-oriented businesses had less severe declines.

Intel (Nasdaq: INTC) also had a sizable loss of more than 1.5%. With several tech giants announcing big innovations in the smartphone and mobile device industry this month, Intel risks getting overshadowed by long-awaited news from its competition. But Intel continues to drive toward a bigger mobile presence, with touchscreen Ultrabooks and tablets that it hopes can make a splash amidst other new competing products.

Finally, DuPont (NYSE: DD) fell about 1.8%. As much as a chemical company may seem tied to the industrial economy, DuPont is also a major player in agriculture. Given the relative inelasticity in demand for food, DuPont has at least some protection against downturns as long as crop prices remain high. Given the drought conditions that have persisted for much of the growing season in the U.S., DuPont doesn't seem vulnerable to a major decline at this point.

Is manufacturing doomed?
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