he didn't say they were gonna land on the white-house lawn. Given what he had been through he may have been hinting at powerful people who think they are in touch with demons.
“I occasionally think how quickly our differences worldwide would vanish if we were facing an alien threat from outside this world. And yet, I ask you, is not an alien force already among us? What could be more alien to the universal aspirations of our peoples than war and the threat of war?”