Israeli attacks have targeted nuclear sites across Iran, including the important uranium enrichment plant at Fordo, a secretive site built inside a mountain. But only the United States is capable of destroying the site as it would take massive, ordnance-penetrator bombs known as 'bunker busters' delivered by American B-2 bombers. Weijia Jiang reports on the decision President Trump will need to make on the U.S. joining Israel in their strikes.