Are US stocks headed for a correction?

Looking around the world, and at a variety of asset classes, it takes some work to avoid an ongoing correction or even a crash in certain corners. That makes me more cautious about our market than I have been in quite some time.

Traders work on the floor of the New York Stock Exchange.
Getty Images
Traders work on the floor of the New York Stock Exchange.

Let's face it: With, or without, government intervention, the Chinese market is crashing. Where it stops is anyone's guess, although the Shanghai Composite looks like it could find an intermediate-term bottom at about 3,000. That's another 600 points, or 16 percent, from here.

Commodities have crashed. From crude oil to copper, basic materials have fallen 50 percent or more over the past year or so. Silver, platinum, palladium, corn, wheat and soy are all well below their most recent peaks. The declines in raw materials have accelerated recently, as a crashing Chinese stock market could lead to further economic weakness there and around the world, curbing demand for natural resources.

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Interest rates are falling, not an encouraging sign of future growth or stable inflation.

And while U.S. markets are not terribly far off their highs, and have traded in an extremely tight range this year, the technical deterioration in U.S. stocks has been, literally, "breadth-taking."

Market leadership has been provided by only a handful of stocks, while everything from high-flying biotech stocks, to oil and gold shares, are providing leadership on the downside.

The number of stocks on the New York Stock Exchange making new 52-week lows ballooned to 485 in Monday's session, while the NYSE advance/decline line has shown rapid deterioration. Market breadth has narrowed, with decliners beating advancers by a 3-1 margin in the last several sessions, hardly the stuff of continued rallies.

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Transportation stocks should benefit from falling oil prices, which drives their operating costs down, but they have fallen almost 12 percent year-to-date. Utilities are down 7 percent for the year, too, while the S&P 500 dipped below its 200-day moving average on Monday. A deeper breech of that technical support level would invite even more selling from chart-watchers and computer-driven traders.

So, are we heading for a fall in the fall?

It certainly seems that the market's composition, leadership, and external forces, do not support predictions of a late summer rally.

Add to those concerns the likelihood of a rate hike from the Federal Reserve, which may be pre-announced by the Fed on Wednesday at the conclusion of this week's policy-setting meeting, and I would recommend taking profits and putting on some protective hedges against a long-only portfolio.

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That could come in the form of simply selling stocks that have run up dramatically this year. Or one could sell calls on the S&P 500, or conversely, buy put options. Either would partially protect a portfolio from a sharp correction in the market.

The cost of portfolio protection can be relatively low, especially when the market is hardly performing like it is ready to make another run for the record books. In fact, a meaningful correction of 10-15 percent is certainly possible, as Wall Street weathers storms that are blowing onshore from around the world.

Markets often climb a wall of worry and this market looks like its legs are weakening as it struggles to make it over the wall.

Commentary by Ron Insana, a CNBC and MSNBC contributor and the author of four books on Wall Street. He is also editor of "Insana's Market Intellgence," available at Follow him on Twitter @rinsana.