In one word: tedious. There's some great acting here, but it's let down by poor pacing and inconsistent character development. In an entirely unnecessary third hour of the movie, a til-then forgettable character tells you exactly what is about to happen, and then you're held hostage in a drab government office to, unsurprisingly, watch what you were told was going to unfold. Skipping out on the more exciting depictions of aftermath from the bombs, Russian espionage, or parallel development programs, you get treated to the drudgery of narrative testimony amid bureaucratic mudslinging in a never-ending parade of established male actors in impeccably tailored 1950s suits.