Though the president obligingly promised $39m for a local unit of Navistar to make electric trucks, it will take time for the firm to scale up production and hire workers.

• 尽管奥巴马允诺纳威司公司的达埃尔克哈特分厂三千九百万美元以制造电动货车，但公司要开始大规模生产，雇佣工人还需时日。