Rivian received a vote of confidence and a boost in stock price recently. Here's why there could be more room to run.With the Trump administration pulling back support for electric vehicles (EVs), adding tariffs to automotive import vehicles and parts, and removing the $7,500 federal EV tax credit, it's going to be tough for the U.S. EV industry to expand in the near term. That creates a scary environment for young EV start-ups such as Rivian (RIVN 0.24%).But here's a little good news for Rivian investors w ...