They are likely expecting the same kind of war we are already in with Russia; in which Russia tries to keep its attacks just below the threshold of open war and its rhetoric and "negotiations" about "seeking peace".

Russia have already attacked subsea cables, openly assassinated targets in many countries, shot down civilian airliners, made multiple drone attacks in Europe, and more. They go for plausible deniability and/or exploit western politicians' desire to avoid conflict and "not escalate" on their watch (and nevermind western politicians already craven to them from the current US President to other parties including AfD, French National Party, etc.).

It is entirely plausible this will escalate to Russia taking out a few satellites, with either kinetic or directed-energy weapons, and the need to replace them. Indeed Russia has been observed testing such systems in the recent years.

There is no need to assume nuke use at all for something to get to the stage of taking out satellites. Taking out satellites with kinetic or energy weapons would definitely leave millions of graduates alive.