US may shoot down spy sat to safeguard tech secrets
Talk about aggressive rights enforcement
In reality, the primary worry for the US military is that the satellite's highly-classified surveillance technology might survive the re-entry and come down in territory controlled by an unfriendly foreign power. It might then be subjected to reverse engineering; or at the very least, enemies of America might learn a lot about US orbital imaging capabilities.
America has sunk billions of "black" dollars into spy satellites, seeking capabilities such as synthetic-aperture radar imaging. This could offer the ability to track individual ships across long ocean passages, for instance, even beneath heavy cloud cover. Rumour has it that the falling spy bird now due to come down might be of this type, perhaps using cunning low-power tech to avoid the use of expensive radioisotope generation.
The idea of secret satellites re-entering uncontrolled and landing fairly intact in the wrong place has long been an established nightmare for the US intelligence community; so much so that it has been used in movie plots. (An example is GI Jane, a film principally about a woman undergoing US Navy SEAL special-warfare training. However, at the end when the SEALs need to go on a real mission so that Demi Moore can win acceptance from the misogynist master chief, they are sent to recover a spy sat downed in enemy territory.)
This time, according to Aviation Week, the Pentagon planners are considering smashing up the satellite before it has dropped properly into the atmosphere. Even the mighty American military (probably) has only a few options here.
One answer might be to fire one of the Missile Defence Agency's (MDA) Ground-Based Mid-course Interceptor rockets at the errant sky-spy. These are designed to put a "kinetic kill vehicle" in the path of a ballistic missile warhead outside the atmosphere. They should be able to knock out the satellite if it passes within reach of the operational interceptor bases (in Alaska and California). The missile technology is still under development, though the MDA has claimed successful tests.
Another option might be the use of an Standard SM-3 interceptor fired from a US Navy Aegis warship. The SM-3 cannot hit targets as high as those reachable with the shore-based missile, but it is said to be capable of dealing with less-capable theatre range ballistic warheads. As the spy sat descends, there may be a part of its trajectory where an SM-3 could nail it - if a suitably armed US cruiser or destroyer were able to reach the right place quickly enough.
These are drastic options, and the fact they are apparently being seriously considered strongly suggests the rogue sat is on course to come down somewhere unfortunate.
No doubt the SEALs and others in the US special-ops community are also considering their options, as well as the missile-defence targeteers. But if the satellite seems likely to crashland deep in eastern or northern Asia, for example - probably in China or Russia - they may not even be able to reach it. In other regions they might be able to reach the secret hardware first and get away again afterwards; but doing so might mean a serious diplomatic incident, or even a shooting war.
All in all, then, the US government might well prefer to wreck the satellite thoroughly while it was still thousands of miles from its impact site and a hundred-plus miles up.
However things turn out, the next few weeks could be interesting ones. ®