He suggests that aliens might simply raid Earth for its resources and then move on: “We only have to look at ourselves to see how intelligent life might develop into something we wouldn’t want to meet. I imagine they might exist in massive ships, having used up all the resources from their home planet. Such advanced aliens would perhaps become nomads, looking to conquer and colonise whatever planets they can reach.”

It makes perfect sense.
If aliens can travel here, obviously they've mastered space travel at light speed, or faster, like wormhole.
There's absolutely NO f*cking way we can avoid contact or if we do get into conflict, we can never win them.
If we do contact with aliens at their planet, observing them, assuming they're primitive, they can't do harm to us anyway on their planet, not to earthlings from here.

At most, only to the earth explorers who go there.
So Stephen Hawking makes no sense... He's not that smart.

He lacks common sense.
You people here are idolizing him, without even daring to question his wisdom, or lack of, when it comes to common sense.

If they have the ability to come to earth and raid our resources, they would've done so long ago.
They're probably already among us, looking like us, and they run the world corporations/banks from proxy.
There's no fight, no way to win a civilization that mastered faster than light space travel.
Stephen Hawking lacks common sense and spiritual wisdom.

If they have the ability to travel here, they would've been able to know the existence of our planet long ago.
If they were ill-intended then they would've raided our planet long ago.
A civilization that has mastered such technology and reached type 1 or above level on kardashev scale would've mastered how to manage resources and their emotional/spiritual development.

Stephen Hawking is bull. I don't trust or believe that guy.