The 30-year Treasury yield climbed another 6 basis points Friday to 5.27%, its highest since 2007. Two days earlier, Warsh had sounded almost pleased that markets were doing some of the work. The 30-year Treasury yield has climbed above the Fed's overnight target rate, leaving long-term borrowing costs increasingly in the market's hands. That leaves more of the tightening in the hands of bond vigilantes, investors who push government borrowing costs higher by demanding better returns. The first means households and businesses absorb higher borrowing costs.