In a bow to America's growing connection to India and its expanding security role in the region, the Pentagon is changing the name of the U.S. military's Pacific headquarters to U.S. Indo-Pacific Command.

Under cloudy Pearl Harbor skies, with the USS Arizona Memorial as a backdrop, Defense Secretary Jim Mattis formally announced the name change Wednesday. He spoke during a leadership change ceremony as U.S. Navy Adm. Philip Davidson took over the command from Adm. Harry Harris, who has been nominated to be the next U.S. ambassador to South Korea.

The change is largely symbolic in nature, and carries no fundamental shifts in troops, military missions or other Pentagon activities. Instead, Mattis said, it's a "recognition of the increasing connectivity between the Indian and Pacific oceans."

Mattis said the new defense strategy released last year "acknowledges Pacific challenges and signals America's resolve and lasting commitment to the Indo-Pacific." And he said relationships with Pacific and Indian Ocean allies have been critical to maintaining regional security.

The U.S. and India have been forging stronger security ties for the last several years, with defense secretaries making more frequent visits and conducting talks on sharing technology.

The two sides also share concerns about maritime security in the Indo-Pacific, including worries about China's increasingly aggressive build-up and militarization of manmade islands in the region.

Concerns about China were evident during the ceremony, along with the ongoing negotiations over a possible summit between President Donald Trump and North Korean leader Kim Jong Un to discuss Pyongyang's nuclear program.

"China continues to improve both the size and the capability of its armed forces, in hopes to supplant the U.S. as the security partner of choice not just in the Indo-Pacific region, but across the globe — and on its own terms," Davidson said as he took over the new command.

Mattis took a subtle swipe at China's "Belt and Road" initiative, which links Beijing's economies to the rest of Asia, the Middle East, Africa and Europe through massive loans and investments.

"The Indo-Pacific has many belts and many roads," said Mattis.

In leaving the command post, Harris laid out the threats across the region. He said North Korea "remains our most imminent threat" and a nuclear-capable Pyongyang is unacceptable.

He added that the U.S. should "cooperate with Beijing where we can" but must stand ready to confront China when necessary.