On 20 April, India’s Chief of Army Staff, General Upendra Dwivedi, touched down in Hawaii for talks with the Commanding General of the US Army Pacific, Ronald P. Clark. The visit comes as Japan – in one of the most significant defence policy shifts in decades – moves to permit the export of military equipment including missiles and advanced technology to partner nations – opening new avenues for Indo-Pacific security cooperation. The timing is clear.
As the crisis in the Strait of Hormuz continues, the Indo-Pacific’s democracies are quietly, but urgently, tightening their security partnerships. For a region already contending with Chinese assertiveness and a North Korea that has conducted seven ballistic missile launches this year alone the crisis has served as a pointed reminder. Open sea lanes and freedom of navigation are by no means guaranteed. For India, the stakes are particularly high. As the world’s third-largest oil importer, its economic lifeblood runs through open sea lanes. Prime Minister Narendra Modi called the disruption in the Strait ‘unacceptable’ as India scrambles to offset the impact by turning to 41 alternative sources of energy imports.
Yet the more consequential danger is that threats to India’s sea lanes do not begin and end in the Middle East. The US-Iran conflict has made plain that strategic waterways can be weaponized with near impunity. That lesson will not be lost on others – least of all China. The risk is that Hormuz ushers in a new template, one in which maritime access becomes leverage, and the norms underpinning a Free and Open Indo-Pacific are eroded by hostile states. In the South China Sea, Chinese naval and coast guard activity reached record levels in 2025, with the Asia Maritime Transparency Initiative reporting a record daily average presence of Chinese vessels in contested waters.
In 2025, it also conducted a record number of live-fire exercises across the region, with seabed survey activities expanding as far as Sri Lanka. No country in the Indo-Pacific understands this pressure better than Japan. Persistent Chinese incursions in its sovereign waters have driven Tokyo to the same conclusion as New Delhi. Sea lane security requires partners with the capability and will to defend it. For both India and Japan, the message is clear. The security of their maritime lifelines is exposed to disruption, not just from distant crises, but much closer to home. This reality is already beginning to shape Tokyo’s strategic thinking. Japan’s Defence Minister, Shinjirō Koizumi, warne d during his inauguration that Japan and its like-minded partners face the most complex security environment since the end of the Second World War.
This view, supp or te d by defence -focused policy shifts, propelled Prime Minister Sanae Takaichi to a landslide February election win. With a strong political mandate, Tokyo is strengthening its defense capabilities while maintaining its exclusively defense-oriented policy. A revision of key strategic documents is scheduled for this year, accompanied by significant budgetary measures fit for the severity of the Indo-Pacific security environment. Japan’s FY2026 defense budget has exceeded US $58 billion for the first time in its history. Substantial sums have been allocated to long-range strike capabilities, and to the introduction of unmanned assets, further enhancing deterrence against China.
Japan has begun procuring stand-off missiles from the US and Norway – intended for defensive use only – while also equipping its destroyers with Tomahawk launch capabilities and domestically produced guided munitions. These capabilities represent the minimum necessary level of defense in an increasingly tense security environment, but they are expected to serve as an effective deterrent against potential Chinese aggression. Tokyo is implementing these changes openly, while keeping diplomatic channels open with the international community. India plays a central role in Japan-led efforts to maintain and strengthen a free and open international order in the Indo-Pacific.
Positioned along critical global sea lines of communication, India is rapidly modernizing its navy, commissioning new vessels at a pace of roughly one every 40 days. In September 2025, the Modi government announced a 15-year plan to strengthen its surface fleet and submarine capabilities. This alignment in Japan and India’s strategic trajectories is no coincidence. The two nations are on the frontlines of intensifying maritime coercion, and both are arriving at the same conclusion: the protection of sea lanes is best secured through a shared approach. Encouragingly, this convergence has already begun taking practical form. In February 2026, Japan, India, and Indonesia conducted a trilateral naval exercise in the Andaman Sea, under Japan’s initiative, as the countries look to build on a steady expansion of joint training and operational exchanges.
Tokyo and New Delhi are also moving into more advanced areas of military cooperation, with the Self-Defense Forces and the Indian Army initiating expert exchanges on amphibious operations. Japan has also agreed to transfer stealth-enhancing radar technology – a highly sensitive strategic technology. This is far from routine military diplomacy. With the US’s attention, and hardware, consumed by the crisis in Hormuz, Japan and India are beginning to step forward as the Indo-Pacific’s leading advocates for a maritime order free from coercion. The Iran crisis has reminded the world that the arteries of global trade are far more fragile than many once assumed.
For the Indo-Pacific, the arteries that power the region’s economies are under an unprecedented level of pressure. As the Indo-Pacific’s two largest democratic maritime powers, Japan and India are uniquely positioned to help anchor a regional order in which campaigns of maritime coercion carry real costs. Their growing co-operation, combined with their respective investment in national capabilities, could form the foundation for a more durable Indo-Pacific security framework.
(The writer, a former Director of Chatham House, is an author.)