Although we don't believe in timing the market or panicking over daily movements, we do like to keep an eye on market changes -- just in case they're material to our investing thesis.

After a big down day for the stock market, it's natural for stocks to regain at least a small portion of their losses on the following day. So far, that's what we've seen in today's trading session, with broader markets posting gains of about a quarter-percent. However, adding to concerns about Syria and other geopolitical hot-spots around the world, news that pending home sales fell 1.3% once again raised the specter of a reversal in the housing market's recovery, which has been one of the linchpins of the overall U.S. economy's strength recently. Although the Dow Jones Industrials (DJINDICES:^DJI) were up about 40 points as of 10:45 a.m. EDT, further bad news on any of several fronts could easily make those gains disappear quickly.

Gains in the oil sector highlight the impact that the threat of Middle East conflict is having on energy markets. With crude prices rising to two-year highs, Chevron (NYSE:CVX) is the biggest gainer in the Dow, rising 2.4%. ExxonMobil (NYSE:XOM) is also near the top of the list with a 1.9% gain. At least for now, triple-digit oil prices have helped both Chevron and Exxon finance record levels of capital expenditures, even on higher-cost projects like ultra-deepwater sites and unconventional land-based production from oil sands and shale plays. But with worldwide presence, both companies are vulnerable to closures of choke points from a rise in armed conflict, and shareholders need to consider that risk even as they expect higher profits from rising prices.

On the other side of the coin, Caterpillar (NYSE:CAT) has fallen almost 1% to lead the Dow's decliners. The stock fell in sympathy with mining-equipment rival Joy Global (NYSE:JOY), which said in its quarterly report that it expects weaker revenue in its 2014 fiscal year, sending its shares down almost 5%. Citing a lack of commodity demand from its customers, Joy beat earnings expectations but said that current revenue levels appear unsustainable based on current conditions. Caterpillar isn't quite as focused on mining equipment as Joy Global is, but with similarly sluggish conditions in its construction-equipment business, Caterpillar has also projected long-term weakness, barring an unexpectedly quick macroeconomic recovery.