"I know Joe. I trust him," Obama said in the Rose Garden as Dunford stood at his side. "Joe is a proven leader of our joint force, including our troops in Afghanistan whom he served Christmas dinner to. He is one our military's most highly regarded strategic thinkers."

Obama also tapped Air Force Gen. Paul Selva, the chief of U.S. Transportation Command, to serve as the next vice chairman of the Joint Chiefs.

Obama highlighted Selva's role earlier in his administration when the Air Force general served as the top military adviser to Secretary of State Hillary Clinton.

"He grasps the strategic environment in which our forces operate," Obama said of Selva. "He understands our military, as powerful as it is, is one tool that must be used in concert with all of the elements of our national power."

Dunford and Selva made no comments during the brief announcement, during which Obama offered a short summary of the challenges that will face the two new top leaders.

"Joe, Paul, we continue to call on our armed forces to meet a range of challenges," Obama said. "We have to keep training Afghan forces and remain relentless against al-Qaida. We have to push back against ISIL and strengthen forces in Syria.

"We have to stand united with our allies in Europe and keep rebalancing as a Pacific power. We have to keep investing in new capabilities to meet growing threats including cyber attack," Obama said.

"As commander in chief, I'll be looking for your honest military advice as we meet these challenges."

The two men must be confirmed by the Senate, but a statement by Senate Armed Services Committee chairman Sen. John McCain, R-Ariz., indicated that their confirmation will be smooth.

"In addition to his leadership of the Marine Corps, General Dunford's exemplary service in Iraq and Afghanistan makes him a strong choice as we confront threats to stability and peace in both countries and throughout the region," McCain said in a statement on his website.

"General Selva's extensive experience as an operational and strategic leader would be a welcome addition to the Joint Chiefs of Staff," McCain said. "The Senate Armed Services Committee will give these nominations prompt and thorough consideration."

The word "prompt" means something different in the Senate than elsewhere, of course. Given Capitol Hill's schedule, it would not be surprising if the nominations are not finalized until the summer.

The National Defense Industrial Association, a major industry trade group representing the defense sector, issued a statement from its board chairman, retired Marine Maj. Gen. Arnold Punaro, saying he "enthusiastically" supports the nominations.

Punaro called Dunford a "Marine's Marine," and also noted that the teaming of Dunford and Selva follows a decades-long tradition of selecting "distinct yet complementary" backgrounds and skillsets for the chairman and vice chairman of the Joint Chiefs.

"The Chairman should ideally hail from the strategic and operational community, having been fully immersed in the perspectives of regional commanders and the combatant commands and should have serious combat experience given the current operational activity," Punaro wrote.

"The Vice Chairman should come from the institutional and managerial side of the defense establishment, aware of the demands of the combatant commands, but be more fully immersed in the institutional processes of the defense establishment along with a comfortable familiarity with emerging technological developments.

Punaro said that Obama and Defense Secretary Ashton Carter "clearly ... have accomplished those complementary roles with these two outstanding nominations."

Dunford, 59, was tapped to be commandant of the Marine Corps following a year and a half as commander of the International Security Assistance Force, leading all U.S. and coalition troops in Afghanistan.

"Fighting Joe" earned his nickname during the 2003 invasion of Iraq, when, as a colonel, he commanded Regimental Combat Team 5 under Gen. James Mattis. A Ranger-qualified infantryman with jump wings and nearly four years spent between Iraq and Afghanistan, Dunford has the physical presence of a warrior: He has a habit of going on seven-mile runs in the heat of the day and completed the Marine Corps Marathon in 2012 with his adult children Patrick and Kathleen at his side.

He's also viewed as one of the Corps' sharpest minds, a graduate of the U.S. Army War College and Marine Corps Amphibious Warfare School with a degree in political science from St. Michael's College in Burlington, Vermont, and dual master's degrees from Georgetown University and the Fletcher School of Law and Diplomacy at Tufts University in Medford, Massachusetts.

But Dunford also has ample experience as a Washington general. He served as assistant commandant under Gen. James Amos from 2010-2012, spearheading programs targeting alcohol abuse among Marines and issuing orders that cracked down on hazing and other "high-risk behavior." He had previously served at the Pentagon as deputy commandant for Plans, Policies and Operations.

During Dunford's Senate confirmation hearing, most questions he fielded had to do with his work in Afghanistan and the future of U.S. operations in the region. He has avoided voicing personal opinions on hot political issues such as ongoing efforts to open ground combat arms and special operations units to female Marines.

In his first six months as commandant, Dunford issued planning guidance that emphasized the Marines' growing relationship with the Navy and its focus on maritime and distributed operations following a decade of land wars in Afghanistan. Dunford also rolled out an ambitious plan to make the Marine Corps force more mature and better trained by adjusting personnel requirements and training for every job and sector in the Marine Corps.

Selva was appointed head of U.S. Transportation Command in May of 2014. Before that, he spent less than two years as the leader of the Air Force's Air Mobility Command and a year as vice command with Pacific Air Forces.

Despite a lack of experience in the fighter community that often dominates Air Force leadership, Selva has risen quickly through the ranks, moving from one prestigious command to another. He is well regarded both inside the Pentagon and in industry.

During his three year stint as assistant to the chairman of the Joint Chiefs of Staff, he was assigned as a military adviser to the State Department — a notable detail, given that it ties him to then-Secretary of State Hillary Clinton. There has been speculation those ties could lead to Selva being tapped as the next Chairman if Clinton wins the White House in 2016.

Although they only overlapped for a few months, Selva and Dunford worked together to facilitate the removal of U.S. equipment from Afghanistan.

If confirmed by the Senate, Selva would replace Adm. James Winnefeld, who became vice chairman in August 2011.

Selva has served as the head of Transportation Command since May 2014. Prior to that, he led Air Mobility Command, during which he oversaw the development of the KC-46A tanker replacement program.

During his tenure at Air Mobility Command and Transportation Command, Selva has been an outspoken advocate for mobility airmen. Last month, Selva told lawmakers that mobility airmen need a rest from non-stop operations Afghanistan, fighting the Islamic State group and helping to contain the Ebola outbreak.

He has also spoken against the corrosive effects of sequestration, warning shortly before the cuts went into effect that slashing the Defense Department's budget would make it harder for mobility airmen to do their job.

"As we negotiate the next several months, if the fiscal uncertainty becomes fiscal reality, and I have to make decisions like grounding parts of the fleet to save money, curtailing air crew training to save money, furloughing civilians to save money, those all induce a level of uncertainty that changes the momentum of who we are and it puts us in a position where it will take a substantial amount of time measured in months to recover," he told reporters in February 2013.

Shortly after taking the helm at Transportation Command, Selva had to face frustrated service members and lawmakers, who were angry because a contractor was taking too long to ship service members' personally owned vehicles overseas.

Days before Selva assumed command, International Auto Logistics took over for the previous contractor. It was the peak season for permanent change-of-station moves, and soon thousands of vehicles were stuck in a backlog, drawing sharp protests from Sens. Dick Durbin, D-Ill., and Thad Cochran, R-Miss.

Since then, Selva has worked with IAL to fix the backlog and make sure there is no similar backlog during this year's PCS peak season. He has also reassured members of Congress that the company has shaped up since last summer.