The events are not comparable. The Chinese test represented wanton disregard for orbital debris, to an extreme degree. The US anti-satellite tests (in 1985 and 2008) were on low-altitude satellites using sub-orbital weapons. This led to much smaller debris plumes that reentered the atmosphere in a short period of time (weeks or months).
Can you see the impact of the debris created by the 1985 ASAT test? No? Can you see the little bump that starts in early 2008 and goes away by 2009 that represents the debris generated by the 2008 US ASAT test? Now look at the impact of the Chinese test, it's night and day. And that's due to the altitude of the event (865 km, well above the outer fringes of the atmosphere, where orbital decay is very, very slow) and the nature of the impact from a counter-orbiting kinetic-kill vehicle, which dumped at least 4 times as much kinetic energy into the impact at the very least.
While launch vehicle and satellite makers have been trying to make their launches cleaner and leave less debris in orbit here comes China to dump in one go the same amount of debris that it takes the ENTIRE WORLD two full decades to generate. In fact, they produced about twice as much debris as the worst case natural space disaster imaginable, two satellites hitting one another (the Iridium 33 / Kosmos 2251 collision).
Look at the graph I posted earlier: http://blogs.nature.com/news/files/debris.JPG
Can you see the impact of the debris created by the 1985 ASAT test? No? Can you see the little bump that starts in early 2008 and goes away by 2009 that represents the debris generated by the 2008 US ASAT test? Now look at the impact of the Chinese test, it's night and day. And that's due to the altitude of the event (865 km, well above the outer fringes of the atmosphere, where orbital decay is very, very slow) and the nature of the impact from a counter-orbiting kinetic-kill vehicle, which dumped at least 4 times as much kinetic energy into the impact at the very least.
While launch vehicle and satellite makers have been trying to make their launches cleaner and leave less debris in orbit here comes China to dump in one go the same amount of debris that it takes the ENTIRE WORLD two full decades to generate. In fact, they produced about twice as much debris as the worst case natural space disaster imaginable, two satellites hitting one another (the Iridium 33 / Kosmos 2251 collision).