Talk of using tactical nuclear weapons against Iran, plus Trump's public swipes at two allies, points to a longer war and higher oil prices and interest rates — bad for borrowers, stocks, and anyone hoping the Middle East settles down soon.

• The Pentagon is reviewing a new deterrence plan built around small, short-range nuclear weapons, aimed at convincing Russia and China the U.S. would actually use them.
• No country has used a nuclear weapon since 1945, and breaking that line first would hand Russia and China an excuse to do the same in Ukraine or around Taiwan.
• Trump is cutting back joint military drills with South Korea while praising Kim Jong-un, and has threatened to bomb Oman over a shipping deal with Iran that would freeze out U.S.-linked vessels.
• Going it alone keeps the war open-ended, which keeps oil and government bond yields high — the 10-year is near 4.7% and oil looks headed toward the $90s.
• High rates are the real danger to stocks: the AI data center boom is being built on debt, and the biggest tech companies are already burning cash to fund it.

Outlook: The nuclear talk is most likely a bluff to rebuild U.S. credibility, but the cost is expensive oil and expensive money for longer, piling more weight on an already strained economy.