140306-N-ZU025-204OKINAWA, Japan (March 6, 2014) Marines assigned to Company F, Battalion Landing Team, 2nd Battalion, 5th Marines, 31st Marine Expeditionary Unit (31st MEU) conduct launch and recovery operations with combat rubber raiding craft from the well deck of the amphibious transport dock ship USS Denver (LPD 9). Denver is assigned to the Bonhomme Richard Amphibious Ready Group and is conducting operations in the U.S. 7th Fleet area of responsibility. (U.S. Navy photo by Mass Communication Specialist 3rd Class Todd C. Behrman/Released)
US Marines conduct amphibious training off Okinawa.. Photo: US Navy

Want to infuriate a Japanese politician?  Tell him Japan must spend more on defense. Want to see incandescent rage? Tell him to spend more on US forces in Japan.

US President Donald Trump has done exactly that, declaring the $2 billion Japan spends on “host nation support” inadequate.  Last summer, he reportedly instructed his national security staff to ask Japan to pay, instead, $8 billion annually.

Is Japan really getting a free ride? Accountants can answer this any number of ways – but consider the replacement cost of American coverage if Japan had to go it alone.

But first, remembering that Japan lives in a tough neighborhood, let’s look at it in context.

Threats on all fronts

China is executing the biggest and fastest buildup of any military since World War II – one that already presents US forces in the Pacific with a serious challenge. Beijing claims Japan’s southern Senkaku Islands, which it insists are Chinese and which it calls the Diaoyu Islands. It also claims the Ryukyu chain.

Seoul has longstanding territorial and historical grievances against Tokyo, but American regional presence dampens Korean behavior.  Remove the Americans, and the Seoul-Tokyo relationship will become more acrimonious.

North Korea loathes Japan and without US forces in situ might upgrade its provocations – and South Korea might not mind.

Looking north, Japan has territorial issues with Russia.

Farther afield, Chinese moves to control the South China Sea – through which Japan’s vital sea commerce flows – continue. More distant threats exist in the Persian Gulf, the source of much of Japan’s energy supply.

If the US military exited, Tokyo would face stark choices: It could acquiesce in Chinese domination of Asia, and perhaps even cede territory – or massively expand its own capabilities.

Let’s cost the latter scenario with a very rough assessment of what Japan would need to acquire if the GIs went home.


Japan currently spends about $50 billion on defense annually. About 40% of budget goes to personnel costs. That’s about $20 billion.

The Japanese Self Defense Forces will need to expand troop strength by perhaps a third to take over the coverage provided by the departed Americans – roughly $7 billion a year in additional personnel costs.

Problem: The JSDF hasn’t met recruitment targets for years (missing by about 25% a year).  To attract and retain manpower Japan must spend more to improve salaries, housing, and terms of service to out-compete the private sector.  Let’s assume an extra $5 billion a year.

To offset recruiting challenges, JSDF could create an effective military reserve system:  Say, $1 billion initially.  Tokyo might also have to consider a draft.  Of course, conscription and the prospect of nuclear weapons will get people onto the streets – a headache US security coverage allows Japan’s leaders to avoid.

Next, let’s consider hardware to cover the areas surrounding Japan and farther afield.


The Maritime Self Defense Force will need another half dozen submarines at about $1 billion each.  That’s $6 billion. And more surface ships will be needed.  Start with a dozen new destroyers at about $500 million each: Another $6 billion.

Japan’s navy will also need enough replenishment ships so the MSDF can patrol farther from Japan – as the US Navy does on Japan’s behalf.  Let’s buy three, at $400 million each. That’s $1.2 billion.

To add heft to the MSDF’s regional presence, it needs four more “helicopter destroyers” that can mount F-35B stealth fighters, adding to the two currently being upgraded. You need three ships to have one operational. While one is at sea, one is being repaired, and another is training to return to sea. At a cool billion a shot, that’s another $4 billion.

As China’s aircraft carriers become fully operational, Japan just might need to buy full-fledged assets of its own – not jury-rigged “helicopter destroyers.” The real thing is expensive – say, $5 billion each.  Let’s buy two. Total $10 billion.

Japan will also need more naval patrol and anti-submarine aircraft. That will be another dozen P-1’s at $150 million a pop.  Total: $1.8 billion.

Although the MSDF can occupy vacated US facilities at Sasebo and Yokosuka, it should have another naval base or two somewhere in Japan to spread assets so as not to be an easy missile target.  Construction isn’t cheap in Japan but let’s suppose it can just modify existing civilian port facilities. Total:  $10 billion.

Air, missiles, space

Now, consider requirements to replace American air coverage.

The Air Self Defense Forces (ASDF) will need a few dozen F35s at about $100 million each. Total:  $3.6 billion.

It will also need re-fueling aircraft to extend the range of “short-legged” F35s.  That’s six refuellers at $150 million each. Total:  $.9 billion

And maybe there will be a need for strategic bombers?  Tokyo would rather not think about that, so we won’t, either.

Replacing the American chunk of Japan’s missile defense system will also cost plenty.

Aegis destroyers: Six at $1.8 billion each for a total of $10.8 billion. More Aegis Ashore systems:  Two at $1 billion each, so $2 billion. Additional Patriot and THAAD anti-missile batteries:  $2 billion.

And Japan will need an offensive missile capability rather than just hoping to swat away incoming. How many? A lot. But lets see what $2 billion gets us.

To make all this work, Japan will need sensor and satellite surveillance networks. That will start at a hefty $10 billion.

And as China moves into space, Japan will need to protect its space resources and interests. Price? $3 billion for starters.

If the US nuclear umbrella folds up, Japan will have to consider the ultimate deterrent. A source tells Asia Times it would only take six months for Japan to weaponized fissile materials, but it is an expensive process. Rough estimate: $2 billion.

And the final price:

This comes, so far, to north of $85 billion.  And don’t forget the long term costs of operating, maintaining, and replacing equipment, and additional troop pay.

This perhaps shakes out as an extra $50 billion or so in defense spending on top of the current $50 billion.  So make it $100 billion a year for Japan’s defense budget for the foreseeable future.

Regardless, Japan is a wealthy country and it has the money.  It just chooses not to spend it on defense.

Indeed, a bigger challenge for Japan’s defense is not paying for it, it is finding enough personnel for an enlarged JSDF and figuring out how to employ new hardware coherently.

Still, there’s yet more to consider when pricing value: GIs could, feasibly, go home, but a treaty alliance could be maintained. So how much is the alliance worth?

Intangible value

The brand value of having the US as an ally, granting the explicit protection of the world’s most powerful military, is massive. Historically, the American defense tie-up provided Japan with the stability necessary to build its economy while underwriting its feasibility as an investment location.

How much has all this been worth to Tokyo?  One might say “priceless” – but how about $500 billion?

Of course, calculating the dollar value of US defense coverage for Japan is an imprecise business.

And there is more to any bilateral defense relationship than simple dollars and cents can quantify.  After all, the US itself benefits from the forward basing in the Pacific that Japan and South Korea provide.

Even so: An annual $2 billion worth of host nation support looks like the bargain of the century.  Given the alternatives, Tokyo might want to flourish its checkbook – even with Trump demanding $8 billion.

Leave a comment

Your email address will not be published. Required fields are marked *