When Chinese-owned Ralls Corp. sued U.S. President Barack Obama back in 2012 over a failed attempt to purchase a wind farm near a naval training facility in the U.S., few people outside of Ralls thought they had a chance.

In an unprecedented development on Tuesday, Ralls proved the naysayers wrong, securing a court victory over the president that could shake up the way the U.S. reviews foreign acquisitions with national security concerns. As WSJ's William Mauldin and Brent Kendall report:

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