Passage Summary: The diplomat points out that before every big war, countries start buying lots of weapons. Because of this, the diplomat thinks that if we just limit weapons through agreements, we can prevent wars from happening.

Conclusion: Arms control agreements will be successful in maintaining peace.

Reasoning: Every major war in the last two centuries was preceded by a rapid increase in weapons acquisition by the participating nations.

Analysis: The diplomat is confusing a correlation (or a necessary precursor) with a cause. Just because every war is preceded by an arms buildup doesn't mean the buildup caused the war; it's much more likely that nations buy weapons because they already intend to fight. The flaw is assuming that by removing a symptom (the weapons), you can remove the underlying cause (the desire for war). Look for an answer that highlights this confusion between a sign of an upcoming war and the actual cause of that war.