Ron Insana, a CNBC and MSNBC contributor and the author of four books on Wall Street, cautions investors not to be alarmed just because and China and other global central banks have been dumping their holdings of U.S. Treasurys.

“Bonds remain the world's safest and most resilient economic bomb shelter,” he wrote for CNBC.

“If someone would have suggested, as recently as six months ago, that China would sell over $150 billion of U.S Treasurys in a handful of months, analysts would have warned of an impending disaster in the U.S. bond markets,” he wrote.

“Forecasters would have said that the dollar would crash, rates would skyrocket and stocks would plunge as America's reliance on the kindness of strangers to finance its budget deficits had finally exhausted their generosity,” he wrote.

“The sale of U.S. Treasurys by the Chinese was far from a repudiation of America's fiscal policies. It was an act of desperation to cover capital flight that has plagued China, and other emerging-market economies in the last several months,” he wrote.

China, the world’s second-biggest economy, has been selling U.S. debt to support the yuan after a surprise devaluation spurred bets on a weaker currency.

Bloomberg News reported in August that China, the largest foreign owner of Treasurys, cut its holdings of U.S. Treasurys that month to raise dollars needed to support the yuan.

Some analysts have warned for years that persistent fiscal deficits made the U.S. Treasury market vulnerable to a reduction in foreign purchases. But many investors say they believe longtime holders such as China won’t sell bonds in a way that threatens to disrupt the market, The Wall Street Journal reported.

“I can’t rule out China being a big risk to the bond market but it’s not something that is keeping me awake at night,’’ James Sarni, senior managing partner at Payden & Rygel in Los Angeles, which manages $95 billion, told the WSJ. “While they may decide to sell more Treasury bonds, the transactions are likely to be done in a prudent way.”

To be sure, others are wary of the trend of foreign nations dumping U.S. debt.

Steven Major, the London-based head of fixed-income research at HSBC Holdings Plc, who stood out in 2014 by correctly predicting that 10-year Treasury yields would fall, cut his end-of-2016 yield forecast to just 1.5 percent, from 2.8 percent previously, Bloomberg reported. That once again puts him at odds with the consensus, with the median of 60 economist predictions compiled by Bloomberg giving a reading of 3 percent.

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