GEOFF BENNETT: But, first, there's been a new incursion by an unidentified object high above American territory, and the U.S. military has shot it down.

It happened this afternoon off Northeastern Alaska, near the Canadian border, as the object flew at 40,000 feet.

National Security Council spokesman John Kirby says it was the size of a small car.

But what it was doing and where it came from are unclear.

JOHN KIRBY, NSC Coordinator For Strategic Communications: We do not know who owns it, whether it's a -- whether it's state-owned or corporate-owned or privately owned.

We just don't know.

And we don't understand the full purpose.

We don't have any -- we don't have any information that would confirm a stated purpose for this object.

GEOFF BENNETT: Kirby says a debris recovery operation is now under way.

Nick Schifrin has been following these developments and joins us now.

So, Nick, what more is known about this object?

NICK SCHIFRIN: As you heard John Kirby say, the U.S. doesn't know the origin or exactly what the object was doing, but it does know it was flying at 40,000 feet.

That is the altitude that civilians -- civilian planes fly.

And that was the crucial variable, these officials say, that led President Biden today to order it shot down and saw it really as a threat to those civilian airliners.

The Pentagon says that it dispatched fighter jets yesterday to observe the object, and they assessed that it was unmanned.

And they say that it's been shot down over frozen water, which could, could make the salvage operation a little bit easier than it's been for that Chinese spy balloon.

GEOFF BENNETT: Well, how does this incident compare to that U.S. fighter jet shooting down that Chinese spy balloon off the South Carolina coast?

NICK SCHIFRIN: Yes, so John Kirby said the two, the object vs. balloon, are different, in terms of apples and oranges, for two reasons.

One is the size.

The Chinese spy balloon, which you see there, was 200-feet-tall, had a payload the size of a jetliner.

And the object today was the size of a small car, and not clear that the object today was capable of any kind of surveillance like the U.S. assessed that spy balloon was for.

But the response, Geoff, was really dramatically different.

The Pentagon yesterday argued that it did not shoot down the Chinese spy balloon over Alaska because it wasn't going to be easy to salvage there.

And the director of operations on the Joint Staff again just yesterday argued that he didn't want to be too quick on the trigger to shoot down the spy balloon because they wanted to watch it as it flew over the United States and observe it and learn from the balloon.

And so a very different response to this object from both the military and President Biden after bipartisan criticism of the president for not shutting down that spy balloon earlier.

But, Geoff again, officials stress that the main difference here was the altitude; 40,000 feet was just too much of a threat to civilian aircraft to allow it to keep floating.

GEOFF BENNETT: Nick Schifrin.

Nick, thanks so much for that reporting.

NICK SCHIFRIN: Thank you.