The US is tightening the economic squeeze on Iran, betting that pressure at home will topple the regime — bad news for ordinary Iranians, who are already suffering, and a high-stakes gamble for Washington.

• The Trump administration now defines success in Iran by three goals: ending the nuclear program, taking the Strait of Hormuz out of Iran's hands, and regime collapse.
• The nuclear program is seen as the easy part, close to a done deal.
• Control of the Strait of Hormuz is treated as non-negotiable, with the aim of putting the key oil shipping lane under some form of international control for good.
• Regime collapse is the hardest goal: the plan is to squeeze Iran's economy until moderates rise up and throw off the IRGC, the hardline military force.
• The IRGC sees this as a fight for its own survival, which makes it dig in harder and makes an uprising less likely.

Outlook: Expect the economic pressure on Iran to keep rising, with the nuclear and Hormuz goals likely settled first and regime change remaining the uncertain, drawn-out piece.