After 9/11, how did Iran's relation to the United States change?

• A. Iran remained hostile and isolated
• B. Iran and the US cooperated more, sharing a common enemy
• C. Iran invaded Afghanistan
• D. Iran severed diplomatic ties with the US

Answer: (B)

The main idea is that when two powers face a common threat, they may cooperate pragmatically even if their broader relationship remains tense. After 9/11, the United States aimed to dismantle the Taliban and disrupt al-Qaeda in Afghanistan. Iran, despite long-standing hostility, had a regional interest in countering extremist groups near its borders. This created a situation where Iran and the United States moved toward limited, practical cooperation—sharing intelligence, assisting in efforts against the Taliban and al-Qaeda, and allowing some logistical support—rather than a full normalizing of relations. This cooperation was tactical and temporary, reflecting how states can align on a security threat even if deeper tensions persist. The other options don’t fit because Iran did not invade Afghanistan, did not sever diplomatic ties, and while relations were not fully friendly, they did become more cooperative in that specific period.