It's a safety thing. Tesla has more tests it needs to compete to say it's as safe as existing brands or close enough to be allowed on public roads. Sometimes the government has to say "We know you want it... but nobody knows what you're getting!"
Can I be the first to call Bullshit? Tesla has met and surpassed DOT standards. what safety issues need to be addressed before the Tesla can be sold? Even the fires that Tesla has experienced are at a much lower percentage than the fires that are fairly commonplace in gasoline cars. So please enlighten us on the "Safety Issues" that need to be addressed before the Tesla can be sold in Iowa.