It has been widely reported that, during his meeting with Prime Minister Keir Starmer last week, President Trump gave his consent to the UK’s proposed deal to transfer sovereignty over the Chagos Islands to Mauritius. However, this is not quite what happened. What he actually said was that he thinks the US ‘will be inclined’ to go along with the deal – but that ‘it is a little bit early, we have to be given the details’.
As the saying goes, the devil is indeed in the detail. Once the President and his team are fully briefed on the situation surrounding the Chagos Islands – and the joint UK-US military base on Diego Garcia – it should become clear that the deal poses a national strategic risk to the US. That is because relinquishing sovereign control of the territory will degrade our ability to protect this vital strategic asset from Chinese attempts to surveil, encircle, and undermine it.
Since the mid-Cold War era, the Diego Garcia military base has been integral to allied security. According to the official American Department of State history of the negotiations, the base – established on the back of a 1966 US-UK agreement – was an integral dimension of nuclear deterrence and the command-and-control of the Polaris/Poseidon submarines in the Atlantic and Pacific fleets in the Cold War. The Department of State account notes how ‘the support provided by Diego Garcia would enable us to operate the Polaris/Poseidon submarines under the same positive command-and-control now in the Atlantic and Pacific’.
The ‘bridge’ function of the Diego Garcia base between the Atlantic and Pacific alliances is even more important now than during the Cold War. Today, the base is a pillar of Nato’s coordination with the Indo-Pacific alliance structure, including the AUKUS agreement and the US bilateral alliance infrastructure, as well as the enhanced US bilateral alliances that sustain deterrence in the face of a post-Cold War threat that will be greater than that of the Cold War.
The Indo-Pacific alliance now struggles to deal with a super-continental Eurasian coalition of nuclear and near-nuclear armed adversaries linked by treaties and bilateral agreements. The coalition is diplomatically aligned, militarily interdependent, shares an active defense-industrial cooperative relationship, and successfully evades international sanctions.
This adversary coalition of China, the DPRK, Iran, and Russia includes three States who are rapidly expanding their nuclear forces. The fourth – Iran – was described by former US Secretary of State Antony Blinken as ‘weeks away’ from having sufficient nuclear material to produce nuclear weapons last year.
Unlike our adversaries of the first and second world wars, this coalition shares borders, and hasn’t got the wartime vulnerability of sea lines of communications (SLOCs) that were so important to securing allied victories in those conflicts. This terrestrial infrastructure has allowed the continued transfer of North Korean troops to support Russian military operations in Ukraine as well as 60 per cent of Russia’s ammunition supply. It has also facilitated the shipment of Chinese dual-use products and technology worth $200 billion (£156 billion) and extensive Iranian drones and ballistic missiles to Russia.
The southern exposure of this coalition is also protected by China’s ten military bases along the Arabian Sea, the Bay of Bengal and the Indian Ocean. Making it harder for the US to use the Diego Garcia facility is a high priority of the adversary coalition, since it is a significant US military base between Singapore and the Suez canal.
As Policy Exchange’s recent report illustrates, if Mauritius is granted sovereignty over the Chagos Islands, its close links to China magnify the risk to our allied security interests. Mauritius has embarked on what has become a well-worn three-stage path leading to Chinese economic and political domination of African, Asian, and Latin American States in the ‘Global South’.
This process is well-advanced in Mauritius. China has achieved local domination of the trading relationship by flooding the local markets with low-cost products. This has evolved into China’s dominance in the local infrastructure under its Belt and Road initiative. This has enabled Beijing to insert a permanent Chinese work force to operate and maintain the infrastructure it has financed.
China has taken over the local information system through its state-controlled firm, Huawei, which has become the dominant telecommunications and network supplier in Mauritius. That in turn has enabled the insertion of China’s surveillance system, Safe Cities. In addition to its capacity to monitor telephone and internet traffic, the system is also connected to a network of 1,000 cage cameras and 3,000 dome cameras which support China’s diplomatic and security aims.
An examination of the government’s rationale for its initiative to hand over sovereignty of the Chagos Archipelago to Mauritius is built on political and diplomatic quicksand. A group representing the indigenous population, Chagossian Voices, is suing them for not being consulted by the Foreign Secretary David Lammy. Awkwardly this came to light after Lammy testified to the contrary in the House of Commons last year. Confidence in the enduring commitment by Mauritius – irrespective of the inclinations of unknown governments long into the future – to of a 99-year lease on the Diego Garcia base for vital UK and US security interests would be a delusion, once the Archipelago is is handed over.
If Mauritius is given the Chagos Islands by the UK, the US is likely to face multiple challenges in trying to keep the base there operational. Lawfare, Chinese attempts to coerce Mauritius into interfering with the exclusive access of the UK and US to the satellite-enabling electromagnetic spectrum around Diego Garcia, or general disruption of base operations are among just a few of the issues that could be expected as a result.
This much is clear: the UK’s surrender of sovereignty over the Chagos Islands would imperil the national security of both Britain and the US. The deal should not go ahead.