Japan's ruling parties agreed Friday that the country should pledge to acquire a "counterstrike capability" to address the rapid deterioration of the regional security environment, heralding a major shift in the nation's security policy.

The Liberal Democratic Party had advocated obtaining an enemy base strike capability, while its junior coalition partner Komeito, known as a pacifist party, had been wary that such a move would constitute a change in Japan's exclusively self-defense-oriented policy.

The Maritime Self-Defense Force's Aegis-equipped Maya destroyer launches a new Standard Missile-3 Block 2A interceptor on Nov. 16, 2022, in the Pacific Ocean. (Photo courtesy of the Maritime Self-Defense Force)(Kyodo)

The capability, which would allow Japan to fire upon and disable enemy missiles before they are launched from foreign territory, remains controversial among legal experts, given that Japan has pursued pacifism under its war-renouncing Constitution since 1947.

Obtaining a counterstrike capability is expected to be declared in the National Security Strategy, the government's long-term security and foreign policy guidelines, scheduled to be updated by the end of this year.

The ruling bloc left some ambiguity regarding the conditions, targets and timing for counterattacks, which observers said could raise fears that Japan may attack countries arbitrarily, possibly destabilizing regional security.

Ruling party lawmakers said that should the government get approval from the Diet for a declaration that Japan has been attacked or an attack on a friendly country represents a threat to Japan's survival, the counterstrike capability could be activated "as a bare minimum measure."

The two parties agreed that targets of potential counterstrikes should be decided on a case-by-case basis, according to the lawmakers. The strikes should be carried out on "military targets" in principle, LDP lawmaker Hiromichi Kumada told reporters.

In its proposal to the government in April, the LDP argued that targets should include "command and control functions" in addition to missile bases, while Komeito has been reluctant to expand the definition of possible targets.

"I believe that strengthening the nation's missile defense capability to the maximum level before (acquiring) a counterstrike capability is a major premise of the two parties' agreement" that was reached at a working-level meeting, said Kumada, a member of a ruling bloc study group on national security.

The parties have confirmed that such a capability would be used as part of exercising the right of self-defense and not for a pre-emptive attack, the LDP and Komeito lawmakers said.

Members of the Liberal Democratic Party and its junior coalition partner Komeito meet to discuss national security strategy in Tokyo on Dec. 2, 2022. (Kyodo)

On Thursday, Komeito approved the planned counterstrike capability at a party meeting, after focusing discussions with the LDP on issues such as the conditions for utilizing such a capability and the potential targets for a counterattack.

Komeito also gave the green light for the designation "counterstrike capability," while the LDP had originally employed "enemy base strike capability" -- an expression that could imply pre-emptive attacks would be allowed.

Keiichi Ishii, secretary general of Komeito, told a press conference earlier Friday that he believes Japan would "maintain the exclusively self-defense posture of the (war-renouncing) Article 9 of the Constitution, even after Japan has a counterstrike capability."

Ishii has pointed to the need for a counterstrike capability in consideration of the growing security threats posed by nuclear-armed North Korea and China.

Since the start of this year, North Korea has fired ballistic missiles at an unprecedented pace in violation of U.N. Security Council resolutions, amid concern that the nation may carry out its seventh nuclear test, the first since September 2017.

China has also been intensifying its maritime activities in the Indo-Pacific region, while the country under President Xi Jinping's leadership has been trying to bolster its military clout in an apparent bid to challenge the regional influence of the United States.

The Japanese government under Prime Minister Fumio Kishida aims to revise the National Security Strategy for the first time since it was adopted in 2013, along with two other key defense-related documents.

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