1. First Contact Could Lead to Invasion
If aliens find us before we find them, it may not be a peaceful exchange. A civilization advanced enough for deep space travel would not cross the galaxy just for a friendly visit. They might arrive seeking resources or data.
If they see humanity as primitive or unimportant, they could easily invade. Our technology would likely be no match for theirs. In the worst case, they could strip Earth of its minerals, destroy infrastructure, and leave us behind in a broken world.
