When Indonesia’s Finance Minister Purbaya Yudhi Sadewa floated the idea last week of charging a toll for vessels passing through the Strait of Malacca – inspired by Iran’s moves in the Strait of Hormuz – it set off alarm bells among insurers and Asian importers.

While Indonesia quickly walked back the suggestion, it underscored a growing reality, analysts say: what was once a rules-based order governing maritime navigation is becoming a more dangerous, expensive, and, above all, politicised business.

“We have not seen the oceans this turbulent and dangerous,” said Elisabeth Braw, senior fellow with the Atlantic Council’s Scowcroft Center for Strategy and Security, since “when countries met to establish rules” decades ago.

For as long as it has existed, shipping has been a dangerous endeavour, subject to piracy and sea banditry. But as international trade expanded after World War II, nations got together to establish a maritime order. They signed a flurry of treaties and agreements between the late 1950s and the 90s, aimed at making the oceans safer and free to navigate.

And since maritime transport moves more than 80 percent of goods traded worldwide, those rules enabled global trade to balloon from about $60bn in the 1950s to more than $25 trillion last year, according to the World Trade Organization.

Now, a series of actions by major players — from the United States to Iran, and Russia to China — threaten to rip apart the rules that have helped ships navigate choppy ocean waters, say experts.

The Hormuz battleground

In the Strait of Hormuz, Iran first restricted passage to most ships from early March after the US and Israel launched their war on the country. Then, on April 13, the US imposed a naval blockade on Iranian ships and ports. Since then, the US has captured Iranian ships near the strait, and its troops have boarded other ships hundreds of miles away in the Asia Pacific, which it alleges were carrying sanctioned Iranian oil. Iranian troops, meanwhile, have also captured ships that they say were trying to pass the Strait of Hormuz without their permission, and have fired at some vessels.

These tit-for-tat acts have amplified a global energy crisis, sending gas and oil prices to multiyear highs.

“Even short of a full shutdown, ‘permissioning’ and pressure can impose major costs and uncertainty,” Jack Kennedy, head of MENA Country Risk at S&P Global Market Intelligence, said.

As an example, he pointed to an incident reported by the United Kingdom Maritime Trade Operations tracking group northeast of Oman in which a container ship had been fired on by a gunboat linked to Iran’s Islamic Revolutionary Guard Corps (IRGC). The ship’s bridge suffered significant damage. It was, according to Kennedy, “a show of a calibrated use of force, signalling control without necessarily aiming to halt all traffic”.

Panama Canal too?

On Tuesday, the US and multiple South American and Caribbean nations issued a joint statement accusing China of “targeted economic pressure” and actions that have “affected Panama‑flagged vessels”.

They said China had detained Panama-flagged ships in its ports, adding that these actions were “a blatant attempt to politicise maritime trade and infringe on the sovereignty of the nations of our hemisphere”.

China, however, hit back, accusing the US in particular of hypocrisy, while appearing to deny the claim that it had captured the Panama-flagged ships.

“Who occupied the Panama Canal for a long time, invaded Panama with its military, and arbitrarily trampled on its sovereignty and dignity? Who covets the Panama Canal, seeks to turn this international waterway – meant to remain permanently neutral – into its own territory, and disregards the sovereignty of regional countries? The answer is self-evident,” Lin Jian, a spokesperson for China’s Ministry of Foreign Affairs, said on Wednesday.

The flare-up comes three months after Panama’s Supreme Court scrapped a longstanding concession held by a Hong Kong-linked company to operate the Balboa and Cristobal ports.

That decision came amid sustained US pressure on Panama to curb Chinese influence around the canal. Beijing has condemned the Panama Supreme Court decision.

‘What has changed is the scale’

For the most part, say experts, the legal framework around maritime transit continues to underpin most routine trade.

But, they caution, the number of high‑profile exceptions is rising.

In recent years, disruptions at sea have taken on more structured and strategic forms. In the Black Sea, Russia’s restrictions on Ukrainian exports during the war there triggered global food supply shocks, showing how naval control can be used to exert economic pressure far beyond the immediate conflict zone.

In the South China Sea, China has increasingly been accused of harassing commercial vessels as part of a broader effort to enforce contested territorial claims, though Beijing denies these allegations.

“Maritime action has always been an important aspect to weigh pressure on an enemy’s economy and military – there is nothing new there, but what has changed is the scale, the volume of containers, the size of the global fleet,” said Jean-Paul Rodrigue, professor at the maritime business administration department at Texas A&M University.

Meanwhile, non-state actors have also reshaped risk calculations: Houthis’ attacks in the Red Sea have forced shipping companies to reroute around the Cape of Good Hope.

‘The risk is the precedent’

Taken together, experts say, these developments point to a shift away from predictable, rules-based navigation towards a system in which access, cost, and security are increasingly shaped by power, leverage, and political calculation rather than universally applied norms.

Some non-state actors are also exploiting gaps in enforcement and oversight. In its latest report, the International Maritime Bureau said 2025 saw the highest level of piracy incidents in the last five years.

Meanwhile, the impact of geopolitics is translating into practical operating decisions. Ships diverted away from their usual maritime lanes burn more fuel and spend longer times at sea, pushing operating costs higher. Insurance premiums and war-risk prices also increase, tightening compliance processes. Even short inspections or detentions can trigger cascading disruptions to schedules and cargo commitments, pushing operators to reconsider routing, the flag they bear on their vessels, and port calls to minimise exposure to politically driven delays.

“The risk is the precedent that could be set once multiple states test boundaries – through de facto permissioning, selective enforcement, or threatening tolls or levies in international straits. Then outcomes become more contingent on bargaining and power,” said Kennedy of S&P Global.