Japanese Prime Minister Shinzo Abe will play a key role in hammering out the final details of the Trans-Pacific Partnership.
Washington CNN  — 

The United States and Japan announced big changes Monday to the guidelines that will govern the defense relationship between the two countries going forward.

Under the new guidelines, Japan will be able to defend other countries – like the United States – that come under attack, such as if North Korea were to launch a missile toward America.

Coming nearly 20 years since the guidelines were last updated, a senior U.S. defense official said the announcement was a “big deal” and a “very important” moment in the U.S.-Japanese alliance.

“The threat from North Korea is increasing,” the official said, adding the new directives could lead to more stability on the Korean peninsula and the Asia-Pacific region.

Officials also said that as the weight of the Asia-Pacific region in global affairs has increased, not to mention the Obama administration’s policy of ‘rebalancing’ the country’s focus in that direction, such an update to the U.S.-Japanese alliance was necessary.

But officials dismissed the notion that the new guidelines are a direct response to the economic, political and military rise of China.

“The guidelines are not aimed at any single country other than strengthening the defense of Japan,” the senior official said.

U.S. officials have already discussed in “general terms” the new revisions with Chinese counterparts, according to U.S. officials, and will be briefing the Chinese in greater detail later this week.

READ: White House to unveil boost to U.S.-Japan military ties during Abe visit

Officials said there will also be increased regional and global cooperation between United States and Japan in peacekeeping operations, humanitarian assistance, disaster relief, international surveillance intelligence, reconnaissance operations, missile defense and other areas.

There will additionally be an increase in cooperation within new domains such as improving situational awareness of space and sharing information on threats and vulnerabilities in the cyber realm.

Defense Secretary Ashton Carter, Secretary of State John Kerry and their Japanese counterparts made the announcement today during a press conference in New York.

“The issuance of the guidelines represents a real change, a real improvement in the ability of Japan and the United States to operate together not only in the defense of Japan, but throughout the region and globally,” the official told reporters at the Pentagon in advance of the announcement.

They also come as President Barack Obama prepares to welcome Japanese Prime Minister Shinzo Abe to the White House Tuesday to commemorate the partnership the U.S. and Japan have developed over 70 years since the end of World War II.

The updated guidelines follow a controversial move by the Japanese cabinet last year approving a defense policy that takes a liberal view of the Japanese constitution that allows for Japanese involvement in the defense of its allies. Prior to that, Japanese forces could only act if Japan itself was directly threatened.

When the first such guidelines were issued in 1978, they were essentially restricted to the U.S. defense of Japan. When they were last updated in 1997, they expanded the ability of both nations to cooperate regionally in situations and areas immediately surrounding Japan.

As Japanese capabilities and interpretations of their constitution have evolve in the intervening years, the new guidelines effectively eliminate the previous geographical restriction on U.S.-Japan cooperation and allow the alliance to do globally what had only been possible on a regional basis before.

Much of the specific details of what the United States and Japan will be permitted to do under the new guidelines will be worked out in the days and weeks ahead. But officials said they will not get ahead of the Japanese political process.

“What we do under the new guidelines will be thoroughly consistent with the Japanese constitution, it will be thoroughly consistent with international law, and of course we will be giving full respect to the sovereignty of third countries in the region as we move forward as an alliance,” the senior defense official said.