Oil prices staying flat during the Hormuz shutdown is a fragile calm that likely won't last, which is bad news for anyone counting on cheap gas long-term.

• Oil prices haven't jumped even though the Strait of Hormuz is closed, which is surprising given how much oil moves through it.
• The main reason prices are calm is that China has cut back how much oil it's buying, easing demand.
• The US appears to be holding prices down on purpose, with signs of quiet cooperation between the US and China.
• US oil reserves are nearly drained, so this price control can't continue much longer.

Outlook: Once China's demand returns or US reserves run out, oil prices are expected to spike sharply.