For more than four decades, the investing world operated on a foundational assumption: that a portfolio consisting of 60% stocks and 40% bonds would protect you when markets turned. But these assumptions are taking a hit from sources that rarely deliver bad news about the markets they cover. In fact, Oppenheimer said Monday that the market is seeing things change in a way they haven't since the Great Recession. He has argued since at least 2023 that rates would stay "higher for longer" than consensus expected. His Aug. 3 argument that "the real risk emerges if the AI trade reverses or markets become more worried about government deficits" is a continuation of that multiyear thesis, not a new one.