Are Asteroid Strikes Really a Threat to Humanity?

i've been reading this very cheerful book lately called the precipice, which is all about the exubstantial risks facing mankind sos. The guy wrote that has been looking at all these potential risks to humanity that could wipe us out. And he actually says, asteroid strikes are very, very low on the list, because actually, we know most of the big asteroids that are anywhere near us and it doesn't look like any of them are a threat. So is this actually a sort of theoretical risk that we're doing an experiment against? Well, so i would say we know about the really, really big asteroids. That's what happened in armagaddon. I really love armag