President Donald Trump's tariffs brought U.S. investment-grade bond issuance to a screeching halt this week, but market stress had already been apparent over the past month as jittery investors pushed back on pricing, some bankers said. Since Trump imposed sweeping tariffs on U.S. imports on Wednesday, no new bonds have been priced by investment-grade companies. The halt in offerings followed a period last month when, for the first time since the pandemic, companies struggled to issue bonds at the price they wanted, several bond syndicate bankers said.