Mark Kelly: Elon Musk has accomplished a lot. As an astronaut, I’ve genuinely enjoyed watching SpaceX progress over the last 20 years, and I actually own a Tesla. But for some reason, he just attacked me on Twitter — calling me a “shill”. Why this man — the richest person on earth, the CEO of a few big companies, the President’s best buddy — is spending his time attacking people on the internet is beyond me. Now, he can go to war behind his keyboard all he wants. It’s a free country. But I’ve launched into orbit 4 times, I flew 39 combat missions in Desert Storm, and I held my wife’s hand in the hospital after she was shot in the head. I don’t scare easily, and I don’t really care what h