Stagflation is rare, but it's one of the toughest environments for a bond portfolio. When low growth and high inflation hit at the same time, it can get ugly for all bond asset classes in a hurry.In recent times, 2022 provided an example of what it can look like. The Vanguard Total Bond Market ETF (BND +0.18%) dropped by 13%. Long-term Treasuries did even worse. Even inflation-protected bonds, which should provide some protection during these environments, took a hit.With inflation expectations rising and G ...