The US is squeezing Iran's economy harder, and history says that path leads to higher gas prices, more attacks on oil shipping, and eventually more war — bad news for American drivers and shaky markets.

• The Treasury has started a global campaign to cut off every source of money reaching Iran, calling it an economic D-Day.
• Sanctions and blockades like this almost never topple a regime — Germany, Japan, Iraq, and Russia all hardened instead, and several ended in shooting wars.
• Iran is already hitting back around the Gulf, and if it goes after UAE or Saudi oil, US gas and diesel prices jump — which pushes food prices up too.
• Scott Bessent has admitted he is holding back on China because harder action could blow up the world financial system.
• With US debt at $40 trillion and interest now the biggest item in the budget, there is little room to bail anyone out if a big bank or country cracks — and the little guy pays, like in 2008.

Outlook: The riskiest stretch runs through January, when the strategic oil reserve runs thin and Iran has the most incentive to push before a new Congress resets everyone's calculations.