In a landmark decision, the U.S. Department of Transportation ruled on Wednesday that Kuwait Airways’ longtime boycott of Israeli passengers violates America’s anti-discrimination laws. The airline says it maintains the ban out of deference to Kuwait’s own laws against doing business with Israel. But that rationale will no longer fly in the United States.

“We expect [Kuwait Airways] to sell tickets to and transport Israeli citizens between the U.S. and any third country where they are allowed to disembark based on the laws of that country,” Blane Workie, the Department of Transportation’s assistant general counsel for enforcement, said in a letter to the airline. “Any airline that wishes to operate in the U.S. should know that we will not tolerate discrimination of any kind in our skies,” Transportation Secretary Anthony Foxx told the AP.

The decision came in response to a complaint filed in 2013 by Israeli Eldad Gatt, who was unable to book a Kuwait Airways flight from New York’s John F. Kennedy Airport to London’s Heathrow because the airline’s booking system would not permit him to select Israel as his passport-issuing country.

Beyond impacting Kuwait Airways, the decision does not bode well for the Boycott, Divestment and Sanctions movement against Israel. Northwestern University law professor Eugene Kontorovich said that while the ruling itself had only a limited direct application to particular airlines that boycott Israelis, it “is a good precedent that discrimination against Israelis under the name of ‘boycott’ is impermissible under U.S. law.” In other words, opponents of Israel boycotts in America will now be able to point to the Department of Transportation’s decision to bolster their legal cases against the practice.

“The Administration has determined that commercial boycotts of Israelis constitute unreasonable and illegal discrimination under U.S. law,” Kontorovich added. “And the ruling is entirely indifferent to the fact that that Kuwait justifies its policies as not being against ‘Israelis’ as people, but based on its opposition to the policies of the State of Israel. It is important to note that such discriminatory policies by private companies would get even less deference.”

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