If this is the case, the question turns to how we can survive the impact instead? What kind of shelters would need to be built, how much provisions we'd need an

If this is the case, the question turns to how we can survive the impact instead? What kind of shelters would need to be built, how much provisions we'd need and for how long, etc. The problem is usually multi-faceted, and there is no reason to think something like this would spell doom for the civilization.