Early Monday morning, two mammoth hovercraft blasted in from the sea and stormed ashore near San Diego. The hovercraft dropped their ramps and disgorged military vehicles onto the sand.

America wasn’t being invaded. No, the beach assault by Landing Craft Air Cushion hovercraft was part of a major U.S.-Japanese amphibious exercise at Red Beach, part of the U.S. Marine Corps’ Camp Pendleton in San Diego County.

This kind of landing exercise happens every once in a while at Camp Pendleton, but this time there was a key difference: one of the LCACs was American, the other Japanese.

The exercise, called Dawn Blitz, is not only a key part of America’s so-called “Pacific pivot,” but also a milestone in Japan’s new defense policy. The future of Pacific warfare, pitting the U.S. and its closest friends against a rising China, is being rehearsed on a California beach.

Dawn Blitz, run biannually by the Marine Corps, kicked off earlier this month with participation from Japan, Canada and New Zealand. After a decade of war in Iraq and Afghanistan, the Marines are getting back to their amphibious roots. Dawn Blitz is an signal of that return. It’s also a demonstration to America’s friends and rivals that the U.S. is returning to the Pacific with sharpened claws.

Dawn Blitz 2013 is only the second of its kind held on the West Coast since 2001. The exercise featured many of the core components of modern amphibious warfare, including clearing sea mines, close air support, naval gunfire support, large scale air assaults and good old-fashioned beach landings.

U.S. Marine Corps Ospreys prepare for mass air assault as part of Dawn Blitz. Department of Defense photo

World War II redux

The war game is a showcase of what American ground forces can do in the Pacific. Washington’s evolving war strategy for the region, known as “AirSea Battle,” conjures up images of large swathes of the Pacific where the dominant forms of warfare are fleet versus fleet engagements and sweeping aerial dogfights. That is, campaigns devoid of land battles.

But any future conflict in the Pacific will tread over some pretty familiar geography — the same islands and beaches where American and Japanese troops tore into each other during World War II. In that conflict the U.S. did fight at sea and in the air, but arguably the most important battles were fought on land, to secure sea and air bases for the island hopping campaigns that took the U.S. from Pearl Harbor to Tokyo Bay.

Were it not for the invasion of such islands as Guam, Saipan, Iwo Jima and Okinawa, air and sea forces would have been severely limited in their range and unable to chip away at Imperial Japan. Despite the image of the Pacific theater as one of aircraft carriers, submarines and bombers, the region also consumed roughly a fifth of American land power during the war.

Warfare has changed, but the geography of the Asia-Pacific region has not. In any future conflict, small and otherwise insignificant islands will once again take on an importance far beyond peacetime value. To guard such islands, and take them away from someone else, a nation with interests in the Asia-Pacific has to have amphibious troops. That is, Marines. And America isn’t the only country planning to use them.

Japanaese troops offload LCAC hovercraft after crossing the Pacific. Department of Defense photo

Japan rises

After 70 years Japan is finally building a true amphibious force and the means to support it. Another aspect of this year’s Dawn Blitz is the presence of the largest contingent of Japan’s Self-Defense Forces to ever exercise abroad. Japan sent a thousand personnel and a flotilla of its most important ships to San Diego.

Tokyo’s participation in the exercise reflects the changing perception of threats to Japan, shifting from a Soviet tank attack in the north during the Cold War to recent Chinese claims on Japanese-held islands. In response, Japan has shifted to a “dynamic defense strategy,” in which mobile forces can be deployed to defend — or retake — islands seized by hostile forces.

Three ships, the Aegis missile-defense destroyer Kongo, the helicopter-carrying destroyer Hyuga, and the landing ship Shimokita crossed the Pacific loaded with helicopters and the equipment of the Western Army Infantry Regiment.

The regiment, WAIR for short, is Japan’s nascent amphibious force: a battalion-sized unit stationed near the southern Ryukyu islands and responsible for defending the contested Senkaku islands. For the past several years WAIR has been training in San Diego in increasingly complicated exercises as the Japanese re-learn the ropes of putting troops ashore.

It’s a bitter historical irony: the U.S. Marine Corps teaching Japan how to conduct amphibious warfare. Japan in fact invented modern amphibious methods, particularly ramped, shallow-draft landing craft capable of beaching and offloading infantry. The Marines studied these developments in the 1920s and ‘30s and used Japan’s own tactics against it in the Pacific.

Now seven decades later it’s the Americans who keep these tactics current, using helicopters and hovercraft for over-the-horizon landings, and above all, tightly integrating land, sea and air forces.

U.S. Marine Corps Osprey prepares to land on JS Hyuga. Department of Defense photo

Amphibious reform

Japan until recently refused to maintain amphibious forces, under the justification that such forces are inherently offensive in nature and contrary to Japan’s pacifist constitution.

But with China’s recent saber-rattling in the East and South China Seas, Japan has decided that amphibious forces designed to defend or take back Japanese territory are consistent with its defense policy. But Japan has to re-learn everything, from the basics of coordinating ship-to-shore landings to how to integrate the talents of the Ground, Maritime and Air Self Defense Forces.

Parochialism complicates the reform. An at-times bitter rivalry between the army and the navy has existed for more than a century, and is widely credited as having helped the Allies win World War II. Even during the Cold War the Self-Defense Forces had little impetus to work together. Learning island-hopping tactics may be the easy part compared to overcoming the inertia of history.

Problems aside, Dawn Blitz 2013 is a not-so-subtle sign to the world that the alliance between the United States and Japan is getting stronger. And the United States is eager to see Japan “normalize” — that is, have a normal military unhindered by constitutional impediments, capable of working even more closely with its larger ally.

The sheer vast scale of the Pacific means any military challenge must be met with a multinational response. Dawn Blitz is built from the ground up with allied participation: snipers from New Zealand exercise with their American counterparts, Canadian infantry learn to work with American tanks, and Marine Corps Osprey tiltrotors land on Japanese ships to demonstrate interoperability.

It’s also a powerful lesson to a headstrong China — that in wartime it’s good to have friends.

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