Defense Secretary Ashton B. Carter on Friday urged the newly commissioned officers of the Naval Academy's Class of 2016 to prepare to tackle five challenges facing the nation.

He ticked them off: Russian aggression, the rise of China in East Asia, a nuclear-armed North Korea, Iranian meddling in the Middle East and the battle against the self-declared Islamic State.

“The United States doesn't have the luxury of being able to choose among these challenges,” Carter said. “We have to do it all.”

Carter spoke on a hot, humid day at Navy-Marine Corps Memorial Stadium as the 1,076 graduating midshipmen sat on the field below. Their commencement marks the end of four years of academic and military training at the elite Annapolis school, and the moment when midshipmen receive their degrees and commissions as officers.

Of the five challenges Carter identified, he singled out China's rising economic and military might as the greatest. The United States has been conducting so-called freedom-of-navigation operations and flyovers in the waters around China to demonstrate America's commitment to long-standing ideas about open access to the seas.

“Every port call and flight hour, every exercise and operation, every sailor and every Marine has added a stitch to the fabric of the Asia-Pacific security and stability,” he said.

In the midst of a presidential campaign in which the value of global trade has been questioned, Carter described what he sees as the benefits of open trading among nations and the economic growth it has spurred in East Asia since the end of World War II.

“Economic miracle after economic miracle has occurred there,” he said. “First Japan, then Taiwan, South Korea and Southeast Asia rose and prospered, and now today China and India are doing the same. We want that positive trend to continue because it's been beneficial to the U.S. economy and its interests.”

But American officials have been concerned that China is seeking to establish a new order. The country has made territorial claims outside its traditional waters and built artificial islands. Carter warned China that it can't enjoy the benefits of free trade and an open internet while also limiting freedom.

“China sometimes plays by its own rules,” he said.

Given the depth of American interests in Asia, Carter said, most of the graduating Navy and Marine officers should expect to serve there during their careers.

The Class of 2016 includes 788 midshipmen who were commissioned as Navy ensigns and 256 as Marine second lieutenants. A few graduates don't receive commissions for medical reasons or because they are foreign nationals who are returning to their own militaries.

Almost a quarter of the graduating class are women who for the first time will enter a military in which every job in the Navy and Marines will be open to them.

For that reason, Navy Secretary Ray Mabus, who has championed women in the Navy and Marines, called the Class of 2016 a special group.

“A more diverse force is a stronger force,” Mabus said. “It's not about diversity for diversity's sake.”

The female midshipmen's uniforms symbolized their new equality. For the first time, men and women alike wore trousers and similar high-collared jackets as they walked out onto the field. In the past, the women wore skirts and different jackets.

Before the ceremony began, the soon-to-be officers gathered in excited huddles off the field. Allyson Strachan, 21, said she will be heading to Pensacola for flight training.

“It's everything I've always dreamed of,” she said. “This bond with my classmates is unbreakable and very meaningful.”

Strachan's father served two decades in the Navy and was in the crowd Friday to see her graduate and be commissioned.

“He's very proud,” Strachan said.

Vice Adm. Walter E. “Ted” Carter Jr., the academy's superintendent, said that by some academic and sporting measures, the 2016 class was the greatest ever to pass through the elite military school.

“You have elevated the Naval Academy to a new high,” he said.

But once the celebrations are done, Carter said, the new officers will have a job to do.

“The real work,” he said, “starts now.”

iduncan@baltsun.com

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