Mark Landler
The New York Times

WASHINGTON — With a patrician bearing, nearly three decades of service on the Senate Foreign Relations Committee, a highly decorated combat career in the Vietnam War, even a father who was a diplomat, John Kerry is the very picture of a secretary of state.

“In a sense, John’s entire life has prepared him for this role,” President Obama said on Friday at the White House, as he nominated Kerry to replace Hillary Rodham Clinton, the first step in filling out a national security team for his second term.

Obama praised Kerry, 69, a Massachusetts Democrat, for having been immersed in “every major foreign-policy debate for nearly 30 years.”

But though Kerry would bring even deeper experience to the job than Mrs. Clinton did, his appointment is likely to further centralize policy decisions in the White House, where for the past four years the president and a small circle of advisers have kept a tight grip on issues like Iran’s nuclear program, China, Pakistan, and the winding down of the war in Afghanistan.

“There’s every reason to believe that we’re going to have a very White House-centric foreign policy,” said David J. Rothkopf, the chief executive of the Foreign Policy Group. “Kerry is going to have to show his loyalty and willingness to work within the Obama system.”

In contrast to Mrs. Clinton, whom Obama named to his cabinet after they competed against each other in the 2008 presidential primaries, Kerry has been a loyal supporter of the Obama administration, guiding an arms-reduction treaty with Russia to ratification in the Senate and playing diplomatic troubleshooter for the White House in Afghanistan, Pakistan and Sudan.

He has also figured at critical moments in Obama’s career. At the 2004 Democratic National Convention that nominated him for president, Kerry gave the keynote speaking slot to Obama, then a little-known Illinois state senator, catapulting him to national prominence. In early 2008, Kerry endorsed him over Mrs. Clinton, and this fall he played the role of Mitt Romney in mock debates — sessions that by some accounts put the president’s teeth on edge.
“Nothing brings two people closer together than weeks of debate prep,” said Obama on Friday, looking at a grinning Kerry. “John, I’m looking forward to working with you instead of debating you.”

However lavish Obama’s praise, his instinctive choice for secretary of state was Susan E. Rice, the ambassador to the United Nations, who withdrew her name from consideration after Republicans threatened to block her nomination because of statements she made after the lethal attack on the American Mission in Benghazi, Libya.
Obama, his aides said, likes Ms. Rice’s blunt style and is in sync with her view of foreign policy, which places a premium on aggressively defending human rights.

As a result, Ms. Rice, who is staying in her post, remains a candidate for a major foreign-policy post in the second term, according to administration officials. Thomas E. Donilon, the national security adviser, is expected to stay on for a year or so, but Ms. Rice could be named to his job.