New Delhi, April 19 -- Big banks in America have ridden a dealmaking boom that has helped drive demand for corporate loans and pulled record-breaking fees from the wild swings in financial markets. But the most surprising and intriguing news so far in the past week's earnings parade of the US financial sector was the diverging fortunes of bond traders at Goldman Sachs and JPMorgan Chase.

The war in the West Asia has created a huge amount of uncertainty since the American and Israeli attacks on Iran began at the end of February, but mergers and acquisitions still got done and US commercial and industrial loans jumped by the most in more than three years.

Fund raising by companies was also strong for most of the first quarter, offering ea...