An interesting article in 1966 Popular Mechanics describes potential ways of disarming an orbiting H-Bomb. A manned spacecraft would be dispatched to the potential offending satellite and disable it by the most unimaginative of ways – cutting off its antenna.
Obviously nothing like this have ever transpired (as far as we know) but the seriousness of the article makes it a nice read.
And if this didn’t work, there was always the “duck and cover” defense:
httpvh://www.youtube.com/watch?v=IKqXu-5jw60