Mahaweli Doctrine: Water as foreign policy in Sri Lanka’s national renaissance

IF King Parakramabahu I were alive today, he might ask: Has Sri Lanka forgotten the foreign policy that once made the island prosperous, secure, and connected to the wider world?

- by Prof. Patrick Mendis

The great king understood that water, commerce, and diplomacy were inseparable. The hydraulic civilisation he built in Polonnaruwa, now a UNESCO World Heritage Site, not only fed a unified nation but also generated agricultural surpluses that flowed through the Mahaweli River system to Gokanna—present-day Trincomalee—for trade across Asia. Historical accounts suggest that Sri Lanka exported rice to China and maintained naval forces to protect commercial shipping from piracy. Long before modern theories of economic development emerged, Parakramabahu practiced what might be called “Trade for Peace,” a phrase I later used in one of my books to describe the commercial diplomacy that helped shape the founding of the United States 250 years ago.

I write this essay from Washington, D.C., a few blocks from the White House and overlooking the Potomac River. Like the Mahaweli in Sri Lanka, the Potomac helped shape the American nation’s commercial destiny. President George Washington championed river and canal navigation, laying the foundation for what later became the Chesapeake and Ohio Canal system, which connected the young republic to its interior. President Thomas Jefferson expanded the United States through the Louisiana Purchase and dispatched the Lewis and Clark Expedition along the Missouri and Columbia Rivers toward the Pacific Ocean, seeking new commercial opportunities and trade links with Asia.

The lesson from both Polonnaruwa and early America is remarkably similar: rivers are not merely waterways. They are instruments of national development, commercial connectivity, and strategic statecraft. When linked to visionary leadership, they become the foundations of prosperity, security, and peaceful engagement with the wider world.

From Potomac to Polonnaruwa