While few details are available, Japan’s Kyodo news service reported that a draft plan had been agreed between the United States and Japan in case of a Taiwan emergency.
The draft operational plan was initially proposed by the US Pacific Command (PACOM) and the plan itself was worked out by Japan’s Self Defense Force and the US Marines. The term “emergency” was not defined.
This is the first report of any actual joint planning effort between the US and Japan focused on potential Chinese attacks on Taiwan. While the US has carried out a number of exercises recently with Japan, such as Exercise Resolute Dragon, and with others (but not Taiwan), these exercises were not based on a common operational command.
Under the draft plan the US Marines, assisted by the Japanese army, would set up a base in the Nansei islands, also known as the Ryukyu islands (southern islands) stretching from Japan’s Kyushu to close to Taiwan.
That base, as foreseen in the draft plan, includes US troops and long-range artillery, primarily in the form of the HIMARS (High Mobility Artillery rocket System) multiple rocket system.
The plan did not define which of the Ryukyu islands would serve as the US base, but most likely it would be one of the islands closest to Taiwan. According to Japan’s foreign minister, in early November US Secretary of State Antony Blinken assured his Japanese counterpart that the US pledge to defend Japan included the southern islands – the Nansei chain.
Japan has been increasingly concerned about Chinese actions around these islands, using the Chinese Coast Guard as a front to push China’s territorial claims over at least some of the southernmost islands.
In 2018, then Japanese Emperor Akihito – now Emperor Emeritus – and Empress Michiko visited Yonaguni island, which is the nearest island to Taiwan, a distance of 67 miles. It was an unusual gesture and the emperor went to Yonaguni specifically to show his connection to Taiwan and where, it is said, he “waved” at his friends in Taiwan.
Stymying US military operations
In 2020 a total of 1,161 Chinese maritime patrol ships spent some 333 days around the disputed Senkaku Islands. China terms the southernmost islands the Diaoyu Islands, not Senkaku.
Toshi Yoshihara, Senior Fellow at the Center for Strategic and Budgetary Assessments (CSBA) in Washington, argued that China’s harassment operations are ultimately aimed at gaining effective control of the East China Sea with the goal of stymying US military operations.
Yonaguni has a population of a little more than 2,000. Japan is building an electronic warfare defense system on the island and adding air defense assets, although the full deployment of Japanese personnel is less than 200.
Under the draft plan, US Marines would move the HIMARS system to one of the islands, most likely Yonaguni because of its proximity to Taiwan. Yonaguni has some forested areas, roadways, and an airfield. The runway is 6,562 feet and is suitable for a fully loaded C-130. HIMARS is C-130 transportable.
HIMARS is an advanced multiple launch rocket system built on a wheeled vehicle. Its predecessor, the M270, based on a tracked vehicle, fields the same ammunition and is in the Japanese inventory.
Both systems fire a number of different 227mm (8.9-inch) rockets such as the M26, M30 and M31. The M31 is a guided rocket (GMLRS) that uses GPS and will soon be joined by a longer-range version – about 100 miles.
HIMARS can also fire much larger rockets known as ATACMS, which are 610mm (24-inch) and have a 300km, or 186 mile, range. Even more significantly, Lockheed is working on a new rocket for the system known as PrSM (Precision Strike Missile) which features a multimode seeker.
PrSM, which is expected to enter the inventory in 2025, can destroy enemy air defenses and ships at sea. Even without PrSM, GMLRS is a devastating weapon with a variety of rockets and configurations.
One of the latest carries thousands of tungsten balls, capable of disrupting enemy landing operations. It has been described by one observer as a “long-range shotgun.”
In addition to the Marines, the US Army and Japan (with the tracked version), Taiwan in June signed a deal to buy HIMARS along with Harpoon coastal defense systems.
One of the key benefits of the HIMARS system is “shoot and scoot,” meaning that the system can be driven to a location, rockets launched, and it can rapidly move to another location, making it hard for an adversary to pinpoint HIMARS and destroy it.
Perhaps one of the biggest deficits in the US approach to security in East Asia – aside from the curious policy of strategic ambiguity for Taiwan – is the lack of shared operational planning and a combined command structure.
The lack of planning and coordination makes it almost impossible to deconflict fighting assets in a conflict, and even harder to coordinate and optimize military operations.
Despite having a defense treaty with Japan and making efforts to support Taiwan’s defense needs, the US Defense Department has been reluctant to put together the kind of defense system that could really deter China, preferring, it seems, to operate independently of both allies and friends.
PACOM’s tentative plan, which will be taken up in forthcoming “two plus two” meetings (foreign and defense ministers) between Japan and the United States, will reveal whether the plan will be implemented.
Japanese observers have pointed out that there are difficulties that need to be overcome, including Japanese constitutional limits on its self-defense forces. Putting together such a plan also runs up against strong political factions in Japan, who do not want a confrontation in China.
Japan and China, for example, have agreed to set up a “military hotline” starting in 2022. However, the Japanese went out of their way to “explain” that Japan’s defense minister Nobuo Kishi stressed to his Chinese counterpart, Wei Fenghe, the importance of peace and stability in the Taiwan Strait and the problems in and around the East China Sea, including the waters around the Senkaku Islands.
The Chinese have not confirmed that Japan raised these points. Unlike Kishi who is a civilian politician, Wei Fenghe, China’s Defense Minister, is a military general who commanded PLA rocket forces.