In that case, yes. But note that the S-300s are protected by Tor-M1 tac-SAMs at closer ranges. In the case of our hypothetical, we may add Tunguskas to the list. The outcome of said strike is by no means predetermined, especially of the S-300 is cold to begin with, and only activates its radar once the target is within the engagement envelope.In the case of PRC S-300's being able to be used offensively... The problem as usual is detection and track management. The missiles themselves have sufficient range (depending on type) to cover the ~140 km between the closest points between Pingtan Island and Formosa. However, without the use of AEW, the highest a radar could be mounted is only ~130 m, and that is assuming 76N6 radar on a 39 m mast could be positioned atop Sunlight Rock. What that in turn means is that the GBAD system is unable to even detect targets flying at under 500 m. That leaves the radar systems vulnerable to prosecution by a number of different strike packages. Take LACM like the AGM-109 Tomahawk. If they were used on a seaskimming flight profile, the S-300 radar could at best detect the LACM when they were/are about 4 minutes out. Now if a radar array could not be positioned atop Sunlight Rock but was instead positioned along the coast at sea level, at best there would be about 2.6 minutes between detection and arrival of a LACM strike package. These estimates are assuming that the radar system(s) work as advertised and that there was no opposing DEW. The detection range restrictions come about due to the limitations imposed by the radar horizon.
Provided the scenario you described, and knowledge of the systems location. I'm not talking about GBAD being used to control the airspace, I'm talking about a GBAD-centric IADS using mobility and ambush tactics to inflict inappropriately high costs on the attacker.As this should demonstrate, GBAD systems can make make areas potentially dangerous for flight. They are still unable to attack aircraft before strike packages can be launched against them, short of receiving outside 'help'.
But of course. No third world nation can ever hope for more then that. In fact had the coalition attacked Gaddafi, and discovered that they were losing a few birds a day, with a high sortie rate, due to significant quantities of highly mobile tac-SAMs, they may have well backed off. This probably would have been perceived as a victory (rightly so) for Gaddafi. Naturally most conflicts are limited (as opposed to total) wars. Otherwise the US would not have withdrawn from Vietnam, and the USSR from Afghan.Note the bolded area. The primary limitation stems from a limited commitment amongst the principal actors, not the effectiveness of a GBAD system. The best Libya could have done in the time allowed, would have been to construct an IADS which could potentially have required more assets to 'deal with' that Western nations were willing to provide.
-Cheers