Iran's Fordo nuclear facility, a heavily fortified mountain site, is virtually impervious to attack, except for a specialized 30,000-pound US "bunker buster" bomb. Only the B-2 stealth bomber can deploy this massive munition, designed to penetrate deep underground bunkers. The bomb's unique construction allows it to survive the impact before detonating, making it the only credible threat to the facility.

Prepared by Rachel Morgan and reviewed by editorial team.