Some Asian countries stand to gain if US president-elect Donald Trump pushes ahead with his promised massive tariffs on China and triggers a new wave of factory relocations to the rest of the region.

D onald Trump’s comeback is now certain, after he decisively won re-election to the White House, but there is growing uncertainty over how his second-term administration will deal with the Asia-Pacific—a region of increasing strategic relevance and home to a number of international economic and security concerns for the U.S.

In Northeast Asia, however, the dynamics are different and the amount that countries like Japan and South Korea contribute to their own defenses is high. In 2022, Japan passed an agreement with the U.S. to spend $8.6 billion over five years on hosting ...