Adm. John C. Aquilino, the current head of U.S. Pacific Fleet, has been nominated by the president to lead U.S. Indo-Pacific Command at Camp H.M. Smith — which covers more than half the globe, has seven of the world’s 10 largest standing militaries, and is the “priority theater” for the Defense Department.

If approved by the U.S. Senate, Aquilino would replace Adm. Phil Davidson, who became commander of Indo-Pacific Command on May 30, 2018.

“The Indo-Pacific is the single most consequential region for America’s future,” the Pentagon’s 2019 Indo-Pacific Strategy Report states. “Spanning a vast stretch of the globe from the west coast of the United States to the western shores of India, the region is home to the world’s most populous state (China), most populous democracy (India), and largest Muslim-majority state (Indonesia), and includes over half of the earth’s population.”

Among Aquilino’s ongoing challenges will be a rapidly rising China, a revisionist Russia and an increasingly capable nuclear North Korea.

“As China continues its economic and military ascendance, it seeks Indo-Pacific regional hegemony in the near-term and, ultimately global preeminence in the long-term,” the strategy report said.

Indo-Pacific Command is the largest of six geographic combatant commands defined by the Department of Defense’s Unified Command Plan.

As a geographic combatant command, Indo-Pacom, as it is known, is in charge of using and integrating Army, Navy, Air Force and Marine Corps forces within its “area of responsibility.”

The Hawaii-based command is supported by multiple components and sub-unified commands including U.S. Forces Korea, U.S. Forces Japan, U.S. Special Operations Command Pacific, U.S. Pacific Fleet, U.S. Marine Corps Forces Pacific, U.S. Pacific Air Forces and U.S. Army Pacific.

The selection of Aquilino continues the tradition of selecting a Navy admiral for the joint service Pacific post, which former Hawaii U.S. Sen. Daniel Inouye once called a mainly ”water command” that should be led by an admiral.

In response to a request from Congress for a list of needs to deter an increasingly assertive China, Davidson last spring submitted a $20 billion request for added defense improvements through 2026.

“Without a valid and convincing conventional deterrent, China and Russia will be emboldened to take action in the region to supplant U.S. interests, ” said Davidson’s “Regain the Advantage” report.

A $740.5 billion defense policy bill recently agreed to by the Senate and House Armed Services Committees establishes the Pacific Deterrence Initiative with $2.2 billion in funding for fiscal 2021.

Davidson told the Missile Defense Advocacy Alliance in September that “North Korea, as long as they retain the capability to shoot long-range missiles and to continue to develop nuclear weapons, will remain, really, in my view, our most immediate threat.”

China, meanwhile, is the most significant strategic threat for the United States in the 21st century, he said.