CAMBRIDGE — America's top military officer in charge of monitoring hostile actions by North Korea, escalating tensions between China and Japan, and a spike in computer attacks traced to China provides an unexpected answer when asked what is the biggest long-term security threat in the Pacific region: climate change.
Navy Admiral Samuel J. Locklear III, in an interview at a Cambridge hotel Friday after he met with scholars at Harvard and Tufts universities, said significant upheaval related to the warming planet "is probably the most likely thing that is going to happen . . . that will cripple the security environment, probably more likely than the other scenarios we all often talk about.''
"People are surprised sometimes," he added, describing the reaction to his assessment. "You have the real potential here in the not-too-distant future of nations displaced by rising sea level. Certainly weather patterns are more severe than they have been in the past. We are on super typhoon 27 or 28 this year in the Western Pacific. The average is about 17."
Locklear said his Hawaii-based headquarters — which is assigned more than 400,00 military and civilian personnel and is responsible for operations from California to India, is working with Asian nations to stockpile supplies in strategic locations and planning a major exercise for May with nearly two dozen countries to practice the "what-ifs."
Locklear's two-day visit to New England, which included meetings with students at the Naval War College in Newport, R.I., coincides with the Obama' administration's recent "pivot" to Asia — the recalibration of national security strategy after more than decade of war in the Middle East to reemphasize a region with rising military and economic powers such as China and India and where most US trade links are.
In closed-door discussions Thursday and Friday, Locklear met with security and foreign policy specialists, including the Harvard Kennedy School's Graham Allison, who directs the Belfer Center for Science and International Affairs, and Asia specialist Joseph Nye Jr..
Nye said he briefed Locklear on a trip he made last fall at the behest of the Department of State to meet with the top leaders of China and Japan to urge them to peacefully settle the disputes over islands in the South and East China Seas.
China last month was accused of directing one of its navy radars at a Japanese warship near the islands where both countries assert sovereignty and claims to fishing and mineral rights. It came several weeks after Japan said China took similar action with one of its military helicopters.
"We have an ongoing number of disputes," Locklear said. "It is not just about China and everybody else, because there are disputes between other partners down there, too. Sometimes I think the Chinese get handled a little too roughly on this.
"What we are concerned most about," he added, "is that they work through these things."
A larger concern is North Korea, which in recent days has threatened to launch a nuclear weapon against the United States.
Following Pyongyang's recent long-range missile launch and underground nuclear test, the United Nations Security Council on Thursday voted unanimously to tighten sanctions on the reclusive Communist regime. In response the North Korean government threatened to nullify its nonaggression pacts with South Korea, where the United States maintains a military presence.
Locklear said North Korea's military has taken recent steps to "visibly increase their levels of readiness" along the demilitarized zone that has separated the two Koreas since the armistice halting the Korean War in 1953. "We are watching very closely what's going on and we are prepared to defend the alliance as well as our homeland," he said.
In the interview, he stressed the need for a global set of guidelines for the Internet and cyberspace, which he called the modern version of the 19th century's "Wild West," where "the only security you brought with you was what you carried on you."
"We made cyberspace as kind of an ungoverned territory . . . and we haven't been able to get our arms around how to govern it yet," Locklear added.
But when it comes to pragmatic military planning, Locklear said he is increasingly focused on another highly destabilizing force.
"The ice is melting and sea is getting higher," Locklear said, noting that 80 percent of the world's population lives within 200 miles of the coast. "I'm into the consequence management side of it. I'm not a scientist, but the island of Tarawa in Kiribati, they're contemplating moving their entire population to another country because [it] is not going to exist anymore."
The US military, he said, is beginning to reach out to other armed forces in the region about the issue.
"We have interjected into our multilateral dialogue – even with China and India – the imperative to kind of get military capabilities aligned [for] when the effects of climate change start to impact these massive populations," he said. "If it goes bad, you could have hundreds of thousands or millions of people displaced and then security will start to crumble pretty quickly.''
Bryan Bender can be reached at email@example.com. Follow him on Twitter @GlobeBender