The Chinese are testing us, I think, and our lack of adequate response will spell our doom. Yes, they reported a similar balloon over their land a few days ago, but I doubt the veracity of this claim; they just want to cover their asses. Too bad the downed balloons were powered with moo goo gai pan. 
My mom thinks it’s aliens. She’s losing it. You cross the galaxy in spaceships and drop a balloon to test our defenses? Nah. That’s like discovering the quadratic equation in crayon. I refuse to believe it.