Whilst I'm inclined to agree, it really depends on how the game was modelled. Yeah, sure, if it was essentially a Cold War version of HoI2 (think the Doomsday scenario expanded into an entire new game) then yeah, it'd be a case of whoever had the technology to drop/launch the H-Bomb first would likely win.
However, were it a game with a much more complex, tier-based tech-tree with a much larger emphasis on politics and intrigue, it could work.
Still, I imagine the overriding temptation to just spam nukes would prevail among most players (particularly the AI, a potentially - and very likely - game-breaking aspect indeed), thereby rendering a possibly half-decent game redundant.
Let's face it, the only reason the Cold War didn't turn into the Third World War was common sense and fear of Mutually Assured Destruction - two things nigh-on impossible to teach the AI in any great detail.
I voted for a First World War version of Hearts of Iron for the very reason that such advanced, potentially world-destroying technology is as yet undeveloped, and would only begin to come into question into the 1930s.