This is a fairly underdeveloped concept, and more of an idea I've been throwing around for most of today. Yes, it is based on a modern historical war - namely the Falklands War of 1982.
The Falklands War isn't exactly totally untouched, although it has yet to be seen in any decent RTS context. It does also differ to many a modern conflict; mostly pertaining to its relatively short duration, and the fact that it is a solid example of amphibious warfare. For those that aren't really familiar with the historical events surrounding the Falklands War, you can read up on a brief summary here;
http://en.wikipedia.org/wiki/Falklands_War
In terms of conversion, I'd propose the Battle for Middle Earth 2 as a sound staging point, due to the ease of modification, relative modern engine and for a number of features already implemented. The main focus of the mod would not be to necessarily realistically or accurately / historically depict the Falklands War, moreover to present a nicely set of themed and short multiplayer map campaigns (as well as a few solo missions / skirmish options here and there) that can be played in a number ways by one to six players.
In terms of gameplay, I'd like to very much move away from the classical attrition minded warfare, and move more into maneuver minded warfare instead - try to design gameplay to suit players that favour rapid dominance or combined arms approaches to warfare. Despite the reasonably modern setting and historical background, I don't want to attempt hyper-realism, and would rather focus on goal-orientated and both low and high level strategic gameplay.
Anyway, I thought I'd throw it open to the floor - you'll find that I'm still considering a project to develop for myself now that I'm currently out of project; with Shee Labs moving away from it's older ventures and trying to find some space to develop something new, and with Epic Generals a short step away from new releases, and other projects on closing - I want to get back to the good stuff, instead of finalising and closing

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