India’s trade policy is working great — for Vietnam

The printed circuit board assembly, the camera module, the touch-screen display and the glass cover.

Together, they account for three-fourths of the bill-of-materials cost of a smartphone. Vietnam, the world’s second-biggest exporter of handsets after China, sources these and most other components at zero tariffs from free-trade partners. But India, which has few such accords of its own but is still keen to emulate the manufacturing powerhouse in its neighborhood, has customs duties as high as 22%.