A concern wafting through some corners of Wall Street, which has recently reached me, centers on Bank of America, our second largest bank, with some $3.5 trillion in assets—and in particular, what appears to be $136 billion of unrealized losses on its balance sheet. Those unrealized losses, which show up on the bank’s third-quarter 2023 financial statements, dated September 30, and filed with the Securities and Exchange Commission, represent more than 70 percent of the bank’s tangible book value and derive mostly—$132 billion of the $136 billion, to be precise—from potential losses in the bank’s portfolio of what it calls “held-to-maturity debt securities.”