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A lone mangrove tree at low tide in a polluted area in Pomalaa, southeast Sulawesi, Indonesia (Adek Berry/AFP via Getty Images)
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The roots of statehood: Why coastal ecosystems matter for sovereigntyThe roots of statehood: Why coastal ecosystems matter for sovereignty
In New Caledonia, the famous Heart of Voh mangrove is fading as rising seas blur its once distinct outline. Across the Asia Pacific the same story is unfolding. Mangroves are retreating under the combined pressure of climate change, coastal development and extractive industries.
A symbol that once represented resilience and beauty is giving way to fragility.
Mangroves serve as natural barriers. Their dense root systems absorb wave energy, reduce the impact of cyclones, and slow coastal erosion. In the Philippines, research shows that coastal villages with extensive mangrove cover experienced less damage from typhoons than those where mangroves had been removed. The research also found that the value of mangroves can be very high; saving one life is worth up to US$302,000, and protecting homes from destruction is worth about $53,000.
Beyond physical protection, their economic role strengthens sovereignty further. Indonesia holds nearly 3.4 million hectares, the largest national mangrove stock in the world. According to a World Bank report, Indonesia’s mangroves provide ecosystem services that support human well-being, including fisheries, raw materials, coastal protection, climate regulation, and cultural benefits. On average these services yield $15,000–50,000 per hectare annually.
Sovereignty, usually thought of in terms of treaties and armies, is now undercut by ecological loss.
Yet, despite this strategic weight, mangroves are under relentless assault.
The UN Food and Agriculture Organisation (FAO) reports that over half of mangrove losses in Asia Pacific between 2000 and 2020 were caused by human activity, clearing for aquaculture, urbanisation, and logging. Additionally, the International Union for Conservation of Nature (IUCN) now warns that half the world’s mangroves could disappear by 2050, with the Southeast Asia and the Pacific countries face the sharpest risks.
In Southeast Asia, the South China Sea illustrates the danger. The sea ranks among the world’s biodiversity hotspots, supporting critical marine ecosystems, mangrove forests, and thousands of fish and sponge species. Yet China and Vietnam have expanded artificial islands in the region to reinforce their presence in disputed waters. Large-scale dredging has devastated fragile coastal ecosystems and hastened erosion. These projects may extend authority at sea in practice, but they also weaken the natural foundations of sovereignty by dismantling the ecosystems that secure coastlines.
Recovery efforts to defend against erosion, Pari Island, Indonesia (Bay Ismoyo/AFP via Getty Images)
For Pacific nations, the stakes are existential. In Kiribati, Tuvalu, and Fiji, rising seas are redrawing coastlines. Where mangroves vanish, shorelines recede faster, undermining the baselines from which maritime zones are measured.
While international law traditionally treats baselines as “ambulatory” and shifting with the sea, Pacific Island Forum members declared in 2021 that they will fix their maritime zones regardless of sea-level rise. Even so, the disappearance of coastal ecosystems raises questions of recognition, continuity, and statehood. Sovereignty, usually thought of in terms of treaties and armies, is now undercut by ecological loss.
History reminds us that mangroves have long carried strategic weight. In the Vietnam War, the dense swamps of the Mekong Delta shielded Viet Cong fighters, enabling them to strike and retreat with cover. Moreover, during the Second World War, Allied troops advancing at Cape Gloucester in New Britain were slowed and exposed by mangrove terrain where swamps collapsed communications and frustrated evacuation. Today mangroves no longer shape wars between armies but determine whether states can defend coastlines, sustain populations, and uphold claims.
In efforts to assert sovereignty at sea, managing maritime resources is no longer peripheral. It is central. Studies in Indonesia show that thickening mangrove belts can physically expand a country’s landmass through natural accretion. By trapping sediments and stabilising shorelines, mangroves gradually build land outward. This process not only guards against sea level rise but strengthens states’ positions in maritime claims. Rehabilitation programs therefore are not merely environmental measures. They are sovereignty strategies.
The approach is not theoretical. In Palawan, the Philippines, community partnerships and Indigenous belief systems have revived degraded mangroves, sustaining both fisheries and state authority. In Brazil, granting custodianship rights to local communities curbed illegal logging while boosting crab harvests. Senegal has planted more than one hundred million mangrove trees since 2006, framing them as pillars of national resilience. Even the United Arab Emirates, despite its desert terrain, invests heavily in mangrove planting. These policies signal climate leadership abroad while reinforcing sovereign credibility at home.
The lesson is clear. When governments elevate mangroves from ecological afterthought to strategic asset, they reinforce not just coastlines but sovereignty itself.
Sovereignty depends on the resilience of coastal ecosystems, making swift action essential. In the Asia–Pacific, defence ministries can treat mangroves as natural protection, finance ministries can harness blue carbon markets, and diplomats can raise their profile in climate negotiations. At the same time, donors and development partners should also back coastal communities directly, since sovereignty is exercised not only in international forums but in the daily care of shorelines and fisheries.
Mangroves once shaped wars by concealing fighters and dictating tempo. Today they hold together coastlines that no fleet or fighter jet can defend. Their roots secure territory, sustain livelihoods, and anchor sovereign claims.
The decline of mangroves is therefore not only ecological. It is sovereign erosion. Nations that protect these forests will maintain their borders, their people, and their international standing. Those that neglect them will find sovereignty slipping away not only through conflict or diplomacy but silently as roots wash out to sea.
The fading Heart of Voh in New Caledonia is more than a picturesque loss to a social media post. It is a warning. When mangroves vanish, symbols of identity dissolve, coastlines retreat, and the very reach of sovereignty begins to blur. What disappears first as a line in the landscape soon becomes a line in law, a line in authority, a line in belonging. If states wish to keep their heartlands intact, they must recognise that sovereignty today is rooted as much in mangrove forests.
About the author
Mohd Yunus
Mohd. Yunus is an independent researcher based in Indonesia. He holds a master’s degree in biological sciences from Khon Kaen University, Thailand.
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