Dhaka, April 17 -- The world's poorest nations are once again discovering what it means to be peripheral to power.

In the latest chapter of 21st-century great-power rivalry, Washington and Beijing have locked horns in an economic slugfest that began with tariffs and has metastasized into a geopolitical confrontation with global consequences. The fight was supposed to be about fairness, intellectual property, and national pride. But in the fog of economic war, it is the least-developed countries (LDCs) that are losing the most-quietly, painfully, and with no clear way out.

This trade war began in 2018 as a calculated maneuver by the Trump administration to rectify perceived imbalances in the U.S.-China trade. There were some justificatio...