New Delhi, Jan. 7 -- Location, location, location: Greenland's position above the Arctic Circle makes the world's largest island a key part of security strategy. But for whom?

Increasing international tensions, global warming and the changing world economy have put Greenland at the heart of the debate over global trade and security, and U.S. President Donald Trump wants to make sure his country controls this mineral-rich island that guards the Arctic and North Atlantic approaches to North America.

Greenland is a self-governing territory of Denmark, a longtime U.S. ally that has rejected Trump's overtures. Greenland's own government also opposes U.S. designs on the island, saying the people of Greenland will decide their own future.

The...