[robbedpeter]

At any given moment the distribution is similar, and we track and regulate the orbits, leaving swathes of space open. Everything about the satellites is engineered, including their orbits. Other countries have less stringent standards, resulting in more or less random de-orbits that can drop space junk anywhere in their path, but the US has a lot of forethought put into orbital standards.

Space junk is an issue, but it's not anywhere near crisis level yet.