Mauritian sovereignty over the Chagos Archipelago? Strategic implications for Diego Garcia from a UK-US perspective

Abstract

This article examines the implications for the U.S. military base in Diego Garcia, located in the Chagos Archipelago, in the event that sovereignty of the atoll is ceded from the U.K. to Mauritius. Diego Garcia has become a critically important military base, facilitating U.S. power projection into the Indian Ocean, Middle East and Africa. The legality and future of British sovereignty over the atoll was challenged in 2019 in both the International Court of Justice and United Nations General Assembly. This article finds that Mauritian sovereignty of Diego Garcia would have considerable adverse consequences for U.S. military activity, potentially prohibiting many of the core functions the facility currently performs, as under U.K. sovereignty. Further, this article examines the strategic utility in Diego Garcia for the U.S. and U.K. governments, which demonstrates why these two nations are willing to endure considerable reputational costs and international backlash for retention of the atoll.

KEYWORDS:

• British Indian Ocean Territory
• Chagos Archipelago
• Diego Garcia
• Indian Ocean
• Mauritius

View addendum:

The case for decolonizing the Chagos islands: A response to Bashfield

Acknowledgments

I would like to note my gratitude to the two anonymous reviewers for comprehensive and constructive reports, in addition to Dr. David Brewster, Mr. Luke Dawes and Ms. Amelia Walsh for their valuable feedback. Acknowledgement is due for ANU colleagues Dr. Sue Thompson and Mr. Mark Badger for their advice on earlier iterations of this project. This article evolved from my postgraduate studies at the ANU National Security College and a seminar delivered at the Newcastle Forum for Human Rights & Social Justice, Newcastle University. All errors are my own.

Disclosure statement

No potential conflict of interest was reported by the author.

Notes on contributor

Samuel Matthews Bashfield is a research officer and postgraduate student at the Australian National University, undertaking a Master’s of National Security Policy degree.

Notes

1 The National Security Archive Kissinger Telcon transcripts contain typographical errors.

Additional information

Funding

This work was supported in part by the Department of Defence, Australian Government under the Made for Multipolarity: Operationalising an Indo-Pacific Strategy in the Indian Ocean grant.