Broderick is certainly believable as a young hacker (dig that early 1980's computer tech!) who wants to steal some video games and instead talks the Pentagon's Artificial Intelligence into starting World War Three. What larks, Pip, what larks!
The movie succeeds in part on the charisma of all of its main actors, from the prissy, pissy Dabney Coleman as the Pentagon's chief computer scientist to Barry Corbin (later of Northern Exposure) as a grumpy, salt-of-the-earth General, John Wood as AI-designer Falken, and Broderick and Ally Sheedy as our high-school leads.
But the writing is sharp as well, though Broderick's ability to escape NORAD HQ in Cheyenne Mountain requires a certain suspension of disbelief. It's hard to imagine a big-budget summer movie today ending as this one does -- not with a half-hour action sequence, but with a bunch of people talking to a computer in a room. John Badham keeps things moving nicely, and his matter-of-fact cinematography keeps things rooted in at least the semblance of the real. Recommended.