The ultimate success of the U.S. and Israeli strikes, and so Trump's decision to intervene militarily, depends on how Iran chooses to react. Some analysts fear this action will accelerate Iranian efforts to build a nuclear weapon, with hardliners in Tehran now viewing it as an urgent priority.

Iran just ended its cooperation with international inspectors, suggesting no post-bombing deal is imminent. That may point to a long game of hide-and-seek, punctuated by military action.

The Iranian government has suspended cooperation with the U.N.'s International Atomic Energy Agency until the security of Iran's nuclear facilities and activities is assured.