By blocking a Japanese company’s takeover of U.S. Steel, President Joe Biden said he was protecting good jobs in the American heartland. He may be putting them at risk instead.

Two weeks after the US election, hundreds of allies gathered at the White House to soothe Joe Biden in defeat. Tracking the closed-door bash for clues was a group rarely interested in the routine preening of Washington: arbitrage traders.

Senior administration officials had reservations about calling Nippon Steel’s takeover proposal a “national security risk.”