The article explains the technical basis of why we've spotted them now - basically we were ignoring small, slow moving objects. And there was a sensible point about the "are these aliens" quote. This article is behind a WaPo paywall.
What we know about the four objects shot down over North America
Are these alien craft?...
“I’ll let the intel community and the counterintelligence community figure that out,” VanHerck said. “I haven’t ruled out anything.”
This is not really a confirmation from the government that these might be alien aircraft. It is a comment from the government that they’re not theorizing on a source. It’s like asking a literalist whether the sun will rise in the morning; they have no reason to think it won’t, but they can’t rule out the possibility that it might not.
So he and we can’t rule out that these are alien vessels, but it seems unlikely that aliens traveled through space and rolled up to Alaska and western Canada in small inflatable aircraft.
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Why are there so many objects showing up right now? It probably seems as though the continent is being inundated with flying objects at the moment. But that’s in part because the military has tweaked its radar settings to better detect small, slow objects.
...
As we’ve written, there are a lot of things that might fit into that category. Schoolchildren often conducted an experiment in science class in which they send up a weather balloon to capture images of the curvature of the Earth. It’s not expensive to do! But those will not be registered flights (the way that the scores of weather balloons released by government observers are) and could be the sorts of things that NORAD is now flagging.
...
In the press call this weekend, VanHerck admitted another reason there are more reports of flying objects: There is “a heightened alert to look for this information.” While this isn’t an admission of a political role, it’s obvious that the Biden administration hopes to avoid another situation in which a balloon-like object is floating over the country for a week. There’s little doubt that the military has been given broader clearance to down aircraft as a result.
What we know about the four objects shot down over North America
Are these alien craft?...
“I’ll let the intel community and the counterintelligence community figure that out,” VanHerck said. “I haven’t ruled out anything.”
This is not really a confirmation from the government that these might be alien aircraft. It is a comment from the government that they’re not theorizing on a source. It’s like asking a literalist whether the sun will rise in the morning; they have no reason to think it won’t, but they can’t rule out the possibility that it might not.
So he and we can’t rule out that these are alien vessels, but it seems unlikely that aliens traveled through space and rolled up to Alaska and western Canada in small inflatable aircraft.
...
Why are there so many objects showing up right now? It probably seems as though the continent is being inundated with flying objects at the moment. But that’s in part because the military has tweaked its radar settings to better detect small, slow objects.
...
As we’ve written, there are a lot of things that might fit into that category. Schoolchildren often conducted an experiment in science class in which they send up a weather balloon to capture images of the curvature of the Earth. It’s not expensive to do! But those will not be registered flights (the way that the scores of weather balloons released by government observers are) and could be the sorts of things that NORAD is now flagging.
...
In the press call this weekend, VanHerck admitted another reason there are more reports of flying objects: There is “a heightened alert to look for this information.” While this isn’t an admission of a political role, it’s obvious that the Biden administration hopes to avoid another situation in which a balloon-like object is floating over the country for a week. There’s little doubt that the military has been given broader clearance to down aircraft as a result.