Steven Mnuchin's ultra-long bond idea is an ultra- longshot for US Treasury

New York

ULTRA-LONG US Treasuries look like an ultra-longshot. That's the message from traders, strategists and even duration-starved bond investors about the potential for 50 or 100-year US obligations.

Steven Mnuchin, US president-elect Donald Trump's pick for Treasury secretary, said he would "take a look at everything", in response to a question about those maturities.

The remarks sent 30-year US bonds into a tailspin, even though the Treasury has persistently slapped down the notion. The move sounds reasonable in theory: Long-term interest rates a…