Japan is considering building new destroyers specializing in missile defense as an alternative to an abandoned plan to introduce the Aegis Ashore land-based missile interceptor system, it was learned Thursday.
The government is examining the idea of equipping the destroyers with Aegis Ashore radars and equipment to find and intercept missiles, government and ruling party sources said.
Japan scrapped the Aegis Ashore deployment plan due to technical reasons. But it had concluded a contract on the system with the United States.
The government hopes that the alternative will help reduce the negative effects of the Japanese policy change on its alliance with the United States.
The government hopes to include costs related to the new idea in fiscal 2021 budget requests to be compiled at the end of this month.
The idea adds to three options scrutinized so far — one to place radars on land and interceptor missile launch equipment on sea, another to deploy the Aegis Ashore system on mega-floats on the ocean and the other to increase the number of Aegis ships.
The first option, however, involves the risk of failures to intercept missiles due to a time lag that may occur when information on the missiles picked up on the ground radars is transmitted to the seaborne interceptor missile equipment via a satellite communications system.
Mega-floats are vulnerable to tsunami and torpedo attacks, while the option of increasing Aegis ships faces the issues of costs and manpower shortages.
So the government came up with the idea of building destroyers whose sole purpose will be for missile defense.
While Aegis ships are capable of dealing with attacks from fighter jets, submarines, missiles and others, they cost between ¥120 billion and ¥200 billion per vessel.
On the other hand, ships that specialize in missile defense would only cost “several dozen billion yen,” a government official said.
Meanwhile, Japan has no experience of operating a missile defense-only destroyer.
Furthermore, the Aegis Ashore system needs to be miniaturized in order to fit into a destroyer. The government is working with the United States to examine the matter from a technical perspective, a government source said.
Other expected problems are changes in operational areas due to weather and sea conditions and the need for periodic port calls for crew member replacement, refueling and repair work.
Another headache is the difficulty of realizing a 24-hour, 365-day constant monitoring system, a feature that led to the government’s initial decision to introduce the land-based Aegis Ashore system.
The government is expected to continue discussions on alternatives to the abandoned plan until it draws up the fiscal 2021 budget in year-end.
The government is likely to keep alive the three options devised earlier. It may not narrow down its choices when it puts together the budget requests.