A tiny island off the coast of Japan has just become the centre of attention in the escalating game of brinkmanship being played out in the South and East China Seas.

Ie Shima is only 23 square kilometres large. It has an airstrip, a fishing port and a population of about 4500.

It’s just been attacked by a US Marine Expeditionary Unit (MEU).

It was all just practice.

But the ‘surprise attack’ and rapid invasion of the island in Japan’s Okinawa archipelago demonstrated a key military capability just days before a US Navy destroyer and US Coast Guard vessel ran the gauntlet of the Taiwan Strait into the South China Sea earlier this week.

Beijing’s controversial tactic of simply squatting on contested islands — or manufacturing enormous military bases out of reclaimed reefs and sandbars — has inflamed tensions with Japan, Taiwan, The Philippines, Vietnam and Malaysia.

US Marines 'seize' island Marines and Sailors with the 31st Marine Expeditionary Unit have engaged in a series of joint-training missions to practice capturing a heavily defended island airfield off the coast of Japan's Okinawa.

The United States says it doesn’t care who owns the islands, so long as the surrounding waterways remain free and open to international traffic. But China claims it all — including the air space and shipping lanes — as its sovereign territory.

Now the US Marine Corps says: “We are ready to rapidly seize ground and project lethal combat power”.

ISLAND ASSAULT

Attacking islands in World War II proved enormously difficult, and extracted an expensive toll of lives. But the United States and its allies managed to roll Japanese invasion forces back to their home islands.

Modern warfare makes the prospect of attacking a remote, small but heavily defended outpost even more daunting. So the US Marines are attempting to evolve new tactics to overcome the prospect of missile swarms, intense electronic jamming, and fortified facilities.

But island-seizing will be “critical for us to be able to project power in the context of China,” Marine Corps General Joseph Dunford, chairman of the Joint Chiefs of Staff, told a Senate Armed Services Committee hearing earlier this month.

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“In the South China Sea and elsewhere in the region, we also fly bomber missions, demonstrating a resilient global strike capability that checks Chinese ambition and assures our regional Allies and partners. Throughout the Pacific, our troops exercise and engage with partners to signal our commitment and counterbalance China’s challenges to the rules-based order.”

And one of those ‘signals’ was just issued by US Marines based in the Pacific.

“The Indo-Pacific region is incredibly dynamic, so we prepare and train daily for real world crises,” 31st MEU commanding officer Colonel Robert Brodie said in a Marine Corps statement last week.

The ‘invasion’ of Ie Shima was a practical test of these ideas.

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The 31st MEU is part of the Wasp Amphibious Ready Group, which comprises the fighter and helicopter carrying USS Wasp, along with amphibious dock landing ships and escorting destroyers.

“Over the course of two weeks, the MEU aligned capabilities with these forces and led a small island seizure,” Colonel Brodie said. “We are ready to rapidly seize ground and project lethal combat power.”

THE ‘ATTACK’

According to a US Marine release, reconnaissance troops were first dropped on to the island via a high-altitude, free-fall insertion technique. These then quickly moved into positions where they could observe defenders and disrupt key pieces of defensive equipment.

With the all-clear given, Marine Expeditionary Unit troops swarmed over the horizon from their ships and bases almost 1000km away. They were carried by fast moving, low-flying MV-22 Ospreys, flying with KC-130 tankers to give them the necessary reach.

Invisibly protecting these aircraft were Marine Corps F-35B stealth fighters, also making use of the tankers to extend their range.

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The vertical lift-off and landing Osprey troop carriers dashed in to offload their raiding troops, which quickly made their move to seize and secure the Ie Shima airfield.

Immediately the field was secured, cargo planes waiting over the horizon made their move. These made low-level air drops of equipment, fuel and spare parts. In essence, it was a prefabricated US Marine airport — called an Expeditionary Advanced Base.

This enabled F-35B stealth jump jets to land, be refuelled and rearmed, and assist in securing the island from counter-attack.

Then large lumbering C-130J Hercules aircraft rapidly deployed heavy missile artillery systems to help defeat remaining pockets of resistance, and attack any nearby hostile ships.

Finally, the main body of occupational US Marines from the 3rd Division were flown in from more than 1500km away.

“This entire mission profile simulated the process of securing advanced footholds for follow-on forces to conduct further military operations with rapid redeployment,” a Marine Corp statement says.

GREAT POWER RIVALRY

The 2018 National Defense Strategy listed China as one of the US’s “strategic competitors” as the country grows its influence in the Pacific and Indian Oceans.

“It is critical for us to be able to project power in the context of China, and one of the traditional missions of the Marine Corps is seizing advanced bases,” General Dunford said.

“If you look at the island chains and so forth in the Pacific as platforms from which we can project power, that would be a historical mission for the Marine Corps and one that is very relevant in a China scenario.”

Despite the success, General Dunford told the Senate Armed Services Committee that his Marines’ “competitive advantage had eroded”.

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“China and Russia have capitalised on our distraction and our constraints. They have invested in capabilities specifically designed to challenge our traditional sources of strength and have sought to undermine the rules-based international order that brought prosperity and relative peace for the last seven decades.”

“By investing heavily in the space and cyber domains while expanding air and maritime capacity and militarising disputed land formations, they are developing the ability to deny us access to the East and South China Seas. The intended effect is to weaken our alliance structure in the Pacific and allow Beijing to rewrite the norms, standards, and laws in the region.”