President Barack Obama chest bumps with a graduate during the U.S. Naval Academy graduation and commissioning ceremony Friday in Annapolis, Md.

Annapolis, Md. ? President Barack Obama promised graduating midshipmen at the U.S. Naval Academy on Friday that, as their commander in chief, he will only send them “into harm’s way when it is absolutely necessary.”

In his first address to military graduates, Obama also pledged to invest in the men and women who defend America’s liberty, not just in the weapons they would take with them into battle against 21st century threats.

“I will only send you into harm’s way when it is absolutely necessary, and with the strategy, the well-defined goals, the equipment and the support that you need to get the job done,” the president told more than 1,000 graduates during a sun-splashed ceremony at Navy-Marine Corps Memorial Stadium.

Obama said he has halted reductions in the Navy, is building up the Marine Corps and investing in the hardware — combat ships, submarines and fighter aircraft — they’ll need to do their jobs. He promised higher pay, enhanced child care and improved support and other benefits.

“In short, we will maintain America’s military dominance and keep you the finest fighting force the world has ever seen,” Obama said, as more than 30,000 watched from the stands.

The president also praised the role of Navy SEALS in freeing a U.S. sea captain by killing his Somali pirate captors last month.

“The extraordinary precision and professionalism displayed that day was made possible, in no small measure, by the training, the discipline and the leadership skills that so many of those officers learned at the United States Naval Academy,” Obama said in his first public comments on the matter.

Among those receiving degrees was John S. McCain IV, the son of Obama’s presidential rival, Sen. John McCain, who watched from a front-row seat on the grassy field with his wife, Cindy, his mother, Roberta, and several of his children. Had the Arizona Republican, who also graduated from the academy, defeated Obama, McCain could have addressed the Class of 2009 himself.

Obama and “Jack” McCain, a fourth-generation academy graduate, shared a handshake, an embrace and a few words when the young man was called up to receive his diploma, following in the footsteps of his father, grandfather and great-grandfather.

Obama did not recognize Sen. McCain in his speech; the White House says it was out of respect for the family’s wishes. But the president did say a few words about his rival for the presidency before he left the White House. He praised the senator as he signed legislation giving the Pentagon new power to curtail wasteful defense spending. McCain was a sponsor of the bill.

“Senator McCain couldn’t be here today because he’s making sure he has a good seat to watch his son graduate from the Naval Academy in a few hours, and that’s where I’m headed as soon as I catch my ride over here,” Obama said at the bill signing in the Rose Garden.

Presidents typically deliver the commencement address at one of the service academies each year. Friday’s speech was the third graduation address by Obama in the past nine days.