Book on aliens on Mars

The book is based at a station on Mars. The base was a joint Soviet/US base (this shows how old it is). The US gets a little nuts and sends in soldiers to take it over, then they leave. They leave the commander’s brother in charge. For the most part the two groups get along, even with the outside politics forces at play.

One of the scientists notice that some of their land vehicles were getting wire (fiber optics) round around their wheels in places where none have ever been laid. Further inspection showed that the wire was alien, being repaired, and part of a species of aliens long on Mars (but not the original Martians).

They make contact, the Earthmen declare their independence (I think) and the aliens help them by making a mirror in space and cause a meteor(?) to crash to help the process of making an atmosphere.

It was likely read in the late 80’s or early 90’s.

I’ve looked on several lists of Martian based fiction and cannot find this one and wish to reread it… I’m on a Mars thing right now.