Leah Jacobs has just opened a savings account at the First National Bank. She is asking a clerk about the meaning of the rules and regulations printed on her passbook.

Regulations are being tightened in the wake of the crisis, and like any investment bank, BarCap is vulnerable to international regulators' plans to demand higher levels of capital.

Even as new regulations increase the supply of longer-dated bank debt, others may suppress investors' appetite for it.