Once upon a time—just six years ago, actually—Northeast Asia was a security backwater. China was in the midst of the “peaceful rise” policy advocated by Deng Xiaoping and though her defense budget grew at a prodigious rate, her neighbors were unconcerned.

The main threat was North Korea, which had successfully tested a nuclear weapon in 2006 and had a growing arsenal of conventional ballistic missiles. But even this threat, once a ballistic missile shield were put in place, could be mitigated.

Japan’s defense policy and establishment, aside from upgrading the Ministry of Defense to a cabinet-level role, remained largely unchanged. The defense budget remained largely unchanged, and when it did, it dropped. Life in Japan went on.

But in 2010, things took a dramatic turn for the worse. The detaining of Chinese fishing boat off the Senkaku Islands turned into an international incident, and China began pressing its claim to what it called the Diaoyu Islands. Anti-Japanese rhetoric sparked nationalist riots. Air and naval confrontations began between the two countries in the East China Sea, and continue to this day.

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In North Korea, the ascendence of Kim Jong in 2011 and the continued development of its nuclear and missile programs have raised questions of whether a mere missile shield is enough to protect the country.

For Japan, it’s the same security environment, but in every way worse. Japan’s neighbors are making noise and the defense budget is up—albeit slightly—to pay for new weapons. With that in mind, here are Japan’s five most deadly weapons of war.

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Izumo-class Helicopter Destroyer

Japan’s second run of “helicopter destroyers,” the Izumo class is an evolutionary growth over the earlier Hyuga-class. There will be two so-called “destroyers,” the namesake and an as-yet unnamed second ship currently under construction.

The ships, which feature a full-length flight deck, hangar, and aircraft elevators measure 248 meters long with a beam 38 meters and a displacement of 19,500 tons. The ships have a crew of approximately 470 individuals. The flight deck and hangar are designed to accommodate up to fourteen helicopters, including CH-47 Chinook helicopters. The flight deck is sufficiently large to allow simultaneous flight operations by up to five helicopters.

The Maritime Self-Defense Force describes Izumo as a multi-purpose vessel. The primary stated role is anti-submarine warfare, with the ship embarking Mitsubishi H-60 sub-hunting helicopters. A secondary role is as a disaster relief/humanitarian assistance platform: the Izumo has a 35 bed hospital complete with a surgical suite and accommodations for up to 450 passengers.

A third role was illustrated by Izumo’s smaller sister ship, Hyuga, during the 2013 Dawn Blitz exercises. During Dawn Blitz, Hyuga embarked Japanese marines and Ground Self Defense Force CH-47J and AH-64J helicopters to conduct air assaults.

The most interesting role for the Izumo class would be that of fixed-wing aircraft carrier. Although Japan has not announced plans to use the ships as such, the fact they are large enough to carry the F-35B Joint Strike Fighter can’t be ignored. The F-35B would be useful supporting the Japanese marine brigade in amphibious operations, as well as providing additional fighters to help monitor the Ryukyu and Senkaku Island chains.

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Properly retrofitted to support fixed-wing operations, each Izumo might be able to embark up to a dozen F-35Bs. The question is whether such a small number of aircraft would be worth the astronomical investment, especially a country with as much public debt as Japan.

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Soryu-class Diesel Electric Submarines

Japan’s Soryu-class submarines have been described as the most advanced diesel-electric submarines in the world. Displacing 4,100 tons submerged, the submarines can make thirteen knots on the surface and up to twenty knots submerged. Four Stirling air independent propulsion systems allow the Soryu class to remain underwater longer than most conventionally-powered submarines.

The Soryu class is built by two shipyards, Mitsubishi Heavy Industries and Kawasaki Shipbuilding Corporation. The Soryu class is armed with six bow-mounted torpedo tubes, with a total of 20 Type 89 high-speed homing torpedoes and American-made Sub-Harpoon missiles.

There are currently eight Soryu class submarines, with more under construction. In response to increased tensions with China and a growing People’s Liberation Army Navy submarine fleet, in 2010 Japan decided to increase its own submarine force from sixteen to twenty-two.

The Soryu-class is in the running to replace Australia’s troubled Collins submarines. Australia may require up to twelve submarines. If the Soryus are picked, the first submarines would likely be built in Japan with the rest co-produced in Australia. India has invited Japan to submit the Soryu class for its Project 75I competition, which has a requirement for six diesel electric submarines.

A disadvantage to this otherwise excellent submarine is its relatively short range. The Soryu-class is essentially a defensive submarine meant to cover key invasion routes to Japan: the Tsugaru Strait, Tsushima Strait, Kanmon Strait, and the Soya Strait.

Japan’s submarine fleet would be a major threat to the People’s Liberation Army Navy, which does not have a strong tradition in anti-submarine warfare. Japan has a strong submarine tradition going back a hundred years, and Japanese sub crews are reportedly trained to a very high standard.

Atago-class destroyers

Japan has a large fleet of over 40 destroyers, the result of a hard lesson learned during the Second World War. The Imperial Japanese Navy had insufficient ships to secure its sea lanes, and blockaded by U.S. Navy submarines, life in Japan nearly ground to a halt. The problem has only become more acute since then and, more than any other modern country, Japan relies upon air and sea lanes for her national survival.

Japan’s most capable destroyers are the formidable Atago-class. At 10,000 tons fully loaded and 528 feet long, the Atago destroyers weigh as much as Japan’s World War II era cruisers. The Atago class is an enhanced version of the earlier Kongo class of destroyers, equipped with six more vertical launch cells and a helicopter hangar. Inspired by the U.S. Navy’s USS Arleigh Burke Flight IIA destroyers, they share many of the same sensors and armament.

The Atago class is, like the Burke class, a powerful jack of all trades. The destroyers are equipped with ninety-six Mk.41 vertical launch missile silos, each capable of holding a SM-2 surface to air missiles, SM-3 ballistic missile interceptors, or ASROC rocket-propelled torpedoes. Surface to surface armament consists of eight SSM-1B anti-ship missiles, while guns include one five inch gun and two Phalanx close-in weapons systems. Each Atago can engage submarines with an embarked SH-60J Seahawk helicopter, ASROC, and six deck-mounted Type 73 anti-submarine torpedoes.

Also like the Burke class, the Atagos were designed to excel at air and ballistic missile defense. The U.S.-designed Aegis Combat System makes it a potent air defense platform. Unlike their cousins the Kongo class destroyers, the Atago class was not outfitted from the outset engage ballistic missiles. This is being remedied with a software upgrade.

In response to China’s naval buildup and North Korea’s nuclear program, Japan is building two more Atago class destroyers. When complete, Japan will have eight Aegis destroyers capable of executing a ballistic missile defense mission. As the Aegis/SM-3 combination forms the top tier of Japan’s ballistic missile defense network, each destroyer is truly a guardian of the whole nation.

V-22 Osprey

Japanese marines have been training with the V-22 Osprey since 2013, when they practiced insertions with the U.S. Marine Corps. A sale has been rumored to be imminent. Last week the U.S. Department of Defense notified Congress of a possible sale 17 V-22 Osprey Block C tilt rotor aircraft to Japan.

The deal, a virtual certainty at this point, includes 40 Rolls-Royce engines and 80 pairs of night vision goggles and is worth an estimated $3 billion. It will be the Osprey’s first overseas sale.

China’s claim to and numerous confrontations over the Senkaku Islands necessitates a small, highly mobile force capable of quickly reinforcing or reclaiming the islands. The islands are too small or, in the case of inhabited islands, too thickly populated to support a sizable garrison.

The introduction of the Osprey into the Self Defense Forces represents a leap forward in Japan’s tactical airlift capabilities. The unique aircraft’s combination of cargo capacity, speed and range were major factors in Japan’s choosing. The Osprey can carry up to twenty-four troops to a distance of 492 miles. An Osprey could carry a full complement of Japanese marines to the disputed Senkaku Islands in approximately an hour and a half without refueling, something not possible with Japan’s CH-47 Chinook fleet.

The Ospreys will probably be based at Nagasaki, home of Japan’s new marine brigade. With tanker support, the Ospreys will be able to operate to the farthest reaches of Japan. Six KC-130 aerial tankers were purchased from the U.S. Marine Corps in 2012.