Are temporary price controls ever justified?

Yesterday, the U.S. trade representative announced an investigation into unfair trade practices that could result in a whole new round of import taxes. The Trump administration will be looking into whether more than a dozen countries are producing too much, flooding the U.S. with cheap products, and making it hard for American companies to compete. Then, war is complicating the Federal Reserve's interest rate decision. And later, could price caps help bring down grocery bills?