Higher oil prices look bad for everyday drivers but good for US oil companies and the dollar's global standing, while squeezing rivals like China and Europe.

• Oil is priced in dollars, so when prices rise, demand for dollars rises too, propping up the dollar's role as the world's reserve currency.
• US oil companies profit from higher prices since their production costs don't change much even as what they sell gets more expensive.
• A military strike on Iran could send oil prices soaring, a shock that would hit China and the European Union much harder than the US.
• The strategy is framed as a way to weaken economic rivals while protecting America's financial power.

Outlook: Expect US policy on Iran and oil-producing regions to keep being shaped by this goal of controlling supply and keeping the dollar dominant.