Electricity in Japan may not be back to normal for months

That means factories will operate at reduced levels, which means limited production of cars, electronic components - lots of stuff. At some point those cutbacks will have an effect on supplies in the U.S. (it's already happening in certain industries). One report estimates that the quake will cause a loss of production of 450,000 vehicles in Japan by the end of March. From the NYT:

Tokyo Electric has been using rolling blackouts of up to three hours in designated zones to balance demand and supply. The cuts have at times been poorly communicated, further disrupting businesses already reeling from logistical problems and damage to factories in the north. And Tokyo, more than most places in Japan, is highly dependent on electric trains and subways for commuting, so when there are blackouts, lots of people cannot get to work or easily organize their days.

Already, U.S. auto dealers are reporting dwindling inventory. From the WSJ:

Dealers are bracing for the dearth of new vehicles they see looming later in April. In Omaha, Neb., Mickey Anderson runs a chain of 12 dealerships, including three Toyota stores. He too is running low on Priuses. His Honda store in Kansas City, Kan., still has Fit subcompacts, which are also imported from Japan, but not as many as he'd like. The Japanese auto makers have tried to reassure dealers that there will be adequate supply, despite stoppages at auto and parts plants in Japan. "None of us believe that," Mr. Anderson said.