Farmers are spending more to keep tractors and combines running. Shipping and trucking companies are passing higher costs to retailers, which are beginning to pass them on to shoppers. And local governments are paying hundreds of thousands of dollars extra to fill up school buses. Construction costs could soon rise, too.The source is the sudden surge in the price of diesel, which is quietly undercutting the American and global economies by pushing up inflation and pressuring supply chains from manufacturing to retail. It is one more cost of the war in Ukraine. Russia is a major exporter of both diesel and the crude oil that diesel is made from in refineries.Car owners in the United States have been shocked by gasoline prices of more than $4 a gallon, but there has been an even b …
