DHAKA — Double-digit growth in Bangladesh’s vital garments sector has put an unexpected gloss on an industry battling U.S. tariffs, Indian trade restrictions and continued domestic political upheaval — a perfect storm of internal and external challenges that threatens to substantially crimp that expansion.

The latest trade blow to the ready-made garments (RMG) sector, which accounts for about 80% of the country’s exports and provides employment to millions, came on May 17 when India imposed restrictions on the import of certain goods, including RMGs, at land ports. That move, made in response to a Bangladeshi ban on yarn imports through the same ports, affects approximately 42% of Bangladeshi exports to India and requires the slower and more expensive use of seaports.