A lot changed when President Trump left the White House in 2021 and President Biden moved in. But one thing didn’t: a protectionist effort to bring more production back to the United States and become less dependent on China. Biden’s policy toward China differs from Trump’s, but the goal is the same: To rework supply chains so more crucial goods come from American suppliers and friendly nations and fewer come from China. But economists are starting to warn that this “decoupling” of the two economic powerhouses could backfire and bring more fragility, instead of more self-reliance. Trump's strategy didn't work,...