Three forces behind the regional expansion

1. Stockpiling as a war hedge

The most decisive factor across the region was inventory-building. Companies accelerated production and purchasing to create buffers against possible disruptions to oil, gas, and critical raw-material flows from the Middle East . Reuters noted the stockpiling was particularly visible in Japan, where manufacturing output surged at the fastest rate since February 2014, driven by both new orders and deliberate inventory accumulation . Across Asia, this behaviour inflated PMI output readings without necessarily reflecting stronger final sales .

2. AI-driven semiconductor demand

A genuine bright spot was the tech cycle. Taiwan, South Korea, and Japan all benefited from surging investment in artificial intelligence infrastructure, which lifted orders for advanced chips and electronics . Singapore’s experience was similar, with output jumping 17.6% year-on-year in April on a surge in AI-related electronics manufacturing, enough to offset some of the drag from the Middle East conflict in other sectors .

3. Uneven export and new-order growth

Northeast Asian economies generally saw firmer new-order growth than their Southeast Asian neighbours . ICIS reported in May that cost pressures from the conflict were weighing more heavily on Southeast Asian manufacturers, while northeast Asia’s production gains were supported by companies hedging against further inflation . The J.P. Morgan Global Manufacturing PMI confirmed that the top five spots in national output growth were all held by Asian economies, led by India, Vietnam, Thailand, the Philippines, and Taiwan .

Why the expansion is more fragile than the PMIs imply

Despite the upbeat top-line numbers, several warning signs emerged:

• China’s demand softened: the official NBS new-orders index fell to 49.9, while raw-material stockpiles dipped to 48.6, suggesting manufacturers were not confident enough to keep building inventories .
• Cost pressures stayed elevated, eroding companies’ ability to absorb the inflation shock from the Middle East, with S&P Global noting historically high cost-burden readings across the Asian PMI panel .
• Stockpiling is not permanent demand: if the Iran conflict stabilises or energy prices retreat, the inventory-building that boosted production could unwind, leaving factories with overstock and weaker output.

Morningstar captured the mood bluntly: “Asia PMI headlines seem bright, but underlying data looks grim.”

The bottom line

May 2026 was a month of real but precarious manufacturing growth across Asia. South Korea and Taiwan rode the AI wave to multi-year highs, while Japan and India held firm. China flatlined, and even the strongest figures carried an asterisk: much of the output was built on fear of conflict, not faith in future demand. As long as the Iran war keeps energy prices volatile and supply chains uncertain, Asia’s factory sector may keep expanding—but that expansion will remain fragile and partly artificial.

Three forces behind the regional expansion

1. Stockpiling as a war hedge

The most decisive factor across the region was inventory-building. Companies accelerated production and purchasing to create buffers against possible disruptions to oil, gas, and critical raw-material flows from the Middle East . Reuters noted the stockpiling was particularly visible in Japan, where manufacturing output surged at the fastest rate since February 2014, driven by both new orders and deliberate inventory accumulation . Across Asia, this behaviour inflated PMI output readings without necessarily reflecting stronger final sales .

2. AI-driven semiconductor demand

A genuine bright spot was the tech cycle. Taiwan, South Korea, and Japan all benefited from surging investment in artificial intelligence infrastructure, which lifted orders for advanced chips and electronics . Singapore’s experience was similar, with output jumping 17.6% year-on-year in April on a surge in AI-related electronics manufacturing, enough to offset some of the drag from the Middle East conflict in other sectors .

3. Uneven export and new-order growth

Northeast Asian economies generally saw firmer new-order growth than their Southeast Asian neighbours . ICIS reported in May that cost pressures from the conflict were weighing more heavily on Southeast Asian manufacturers, while northeast Asia’s production gains were supported by companies hedging against further inflation . The J.P. Morgan Global Manufacturing PMI confirmed that the top five spots in national output growth were all held by Asian economies, led by India, Vietnam, Thailand, the Philippines, and Taiwan .

Why the expansion is more fragile than the PMIs imply

Despite the upbeat top-line numbers, several warning signs emerged:

• China’s demand softened: the official NBS new-orders index fell to 49.9, while raw-material stockpiles dipped to 48.6, suggesting manufacturers were not confident enough to keep building inventories .
• Cost pressures stayed elevated, eroding companies’ ability to absorb the inflation shock from the Middle East, with S&P Global noting historically high cost-burden readings across the Asian PMI panel .
• Stockpiling is not permanent demand: if the Iran conflict stabilises or energy prices retreat, the inventory-building that boosted production could unwind, leaving factories with overstock and weaker output.

Morningstar captured the mood bluntly: “Asia PMI headlines seem bright, but underlying data looks grim.”

The bottom line

May 2026 was a month of real but precarious manufacturing growth across Asia. South Korea and Taiwan rode the AI wave to multi-year highs, while Japan and India held firm. China flatlined, and even the strongest figures carried an asterisk: much of the output was built on fear of conflict, not faith in future demand. As long as the Iran war keeps energy prices volatile and supply chains uncertain, Asia’s factory sector may keep expanding—but that expansion will remain fragile and partly artificial.