Let’s see — a Bank of America-hawked fund loses $22 billion in a matter of weeks and the bank scrambles to make investors whole. The subprime mortgage mess is blamed.

As we’ve tried to explain the past few weeks, this current situation in financial markets was years in the making and will take years to unwind. BofA and others tried to pretend that the mortgage business was riskless and — here is where it gets complicated — that the “zero” risk in their mortgage portfolio could secure corporate paper deals and other forms of yet-more risky lending.

Note that by “risky” we do not mean insane or irresponsible — not if you price in the risk you are taking on both sides of the ledger. BofA and some other banks seem to have stopped doing that — only the higher profit margins of subprime and less than primo commerical paper were banked. Risk? Poof.

Until now. BofA is in no-where near the fix that Citigroup find itself in. Still, the correct move is to own up to losses like these, level with investors, and try to move forward.