In 2022, investors were forced to deal with one of the worst market environments in history - both stocks and bonds experienced bear markets at the exact same time, recalls David Dierking, exchange-traded fund specialist and editor of TheStreet's ETF Focus.

Treasuries are supposed to be a safe haven when stocks decline. Instead, they were posting larger losses than the S&P 500. Investors had almost nowhere to turn for protection.

Fortunately, the environment has changed over the past two months. Treasuries have been responding less to the actions of the Fed and more to global recession risks. Stocks and bonds are returning to their traditional inversely correlated relationship. In short, Treasuries are behaving like a safe haven again.

That being said, I believe Treasuries offer a real opportunity in 2023. The global economy is already slowing and will likely continue to do so throughout the year. The Fed has given every indication that it will keep monetary conditions tight to control inflation, even at the risk of entering the US into a deep recession in the process.

That's exactly the kind of environment that could lead to big gains for Treasuries as investors take risk off the table. The home run swing would be the iShares 20+ Year Treasury Bond ETF (TLT).

With a duration of 18 years, it would be best positioned to deliver big share price gains should interest rates continue retreating in 2023, a reasonable assumption if recession risks keep growing.

Long-term Treasuries were a tough sell a couple years ago when yields were 1% or less and there was little share price appreciation potential to be had. With long-term rates around 4% today, I can see the potential for a 20% total return if rates keep declining throughout the year.

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