It really depends on whether one side or the other is willing to go nuclear, first. If a US ally is assaulted with a large conventional attack, the US is not likely to reply with nuclear weapons. It then becomes an old-fashioned slugfest, with the US at a significant disadvantage due to being locally outnumbered with long, vulnerable, logistics and C&C links.
Tactically, no, but strategically, yes. The satellites are needed to keep the intelligence flowing and run the war itself, not the local combats.
A sample scenario would be a strike on communications and intelligence capabilities, followed up by a massive attack on a US carrier group. The carrier group would no doubt do a good job of defending itself, but they're not likely to do anything retaliatory without POTUS direction...which the satellite strike would make far, far more difficult to receive, and the lack of updated intelligence would mean the mobile targets would no longer be where you thought they were.
Over the years, space had made things too easy...too easy to communicate, too easy to navigate, etc. One of the things I'd been involved with over the years are TACSATs; intelligence collectors that can be used directly by local commanders vs. delivering the take in the CONUS and having it process/filtered by non-combat agencies. Studied a lot, never went anywhere. It's not just the empire builders in the CONUS who wanted to retain the status quo; the field commanders didn't want "one more damn trailer."
Ron Wanttaja