It is kind of strange. Apparently we used AIM-9X Sidewinder missiles to shoot down the balloons...at a per unit cost of US$381,069.74. The payload on the first one was the size of a bus if the reporting is correct. Perhaps worthy of a $400k missile. Not sure about the others. F-22's have a 20mm Gatling gun. I would think you could just plink-plink a balloon with a few rounds at a fraction of the cost. Guess not.
We don't know that the others were balloons. Like Rushy said, they're being vague about it.
Descriptions of objects:
First object - Balloon over Montana
Second - "The object was very different to the balloon, the size of a Volkswagen Beetle, and was flying at 40,000 feet without any obvious system of propulsion or control, officials said."
Third - "Officials described the object as smaller than the first balloon and cylindrical. It was also flying at about 40,000 feet when it was shot down."
Fourth - "That object was an octagonal structure with strings hanging off it, but with no evident payload."
But then we have - "On Sunday, the US Senate majority leader, Charles Schumer, who was briefed by the Biden administration before the Lake Huron incident, said the second and third objects were very likely small balloons."
So who the fuck knows. But it's aliens.
https://www.theguardian.com/world/2023/feb/13/what-do-we-know-about-the-four-flying-objects-shot-down-by-the-us