US Secretary of State John Kerry delivers a speech on the US-India Strategic partnership in New Delhi on June 23, 2013. US Secretary of State John Kerry called for a "central role" for India in Afghanistan's 2014 elections as he warned of potential difficulties in the war-torn nation as US forces withdraw. AFP PHOTO/Jacquelyn Martin/POOL (Photo credit should read JACQUELYN MARTIN/AFP/Getty Images) Secretary of State John Kerry asserted Sunday that the United States now has evidence of sarin gas use in Syria and said "the case gets stronger by the day" for a military attack. (credit: JACQUELYN MARTIN/AFP/Getty Images)

WASHINGTON (AP) — In four months as secretary of state, John Kerry has certainly promised great things. Now he has to deliver.

In the Middle East, he has raised hopes his solo diplomatic effort can produce a historic breakthrough ending six decades of Arab-Israeli conflict.

He has pledged to bring Syrian President Bashar Assad’s government to heel and to work with Russia to end Syria’s civil war.

He has suggested rolling back U.S. missile defense in the Pacific if China can help rid North Korea of nuclear weapons. He has hinted at possible one-on-one talks between the U.S. and the reclusive North Korean leader Kim Jong Un if it would help.

Since succeeding Hillary Rodham Clinton as America’s top diplomat, Kerry has issued several as yet undelivered — and perhaps undeliverable — pledges to allies and rivals alike, proving a source of concern for Obama’s policy team. It is trying to rein in Kerry somewhat, according to officials, which is difficult considering Kerry has spent almost half his tenure so far in the air or on the road, from where his most dissonant policy statements have come.

The White House quickly distanced itself from both Kerry’s North Korea remarks and has now, since President Barack Obama’s meeting with Russian President Vladimir Putin in Northern Ireland this past week, seen up close the strength of Moscow’s resistance to Kerry’s Syria strategy.

All the officials interviewed for this story spoke on condition of anonymity because they weren’t authorized to evaluate Kerry’s performance publicly.

Reporting for work at the State Department in February, the former Democratic senator from Massachusetts quickly outlined his ambitions.

Clinton still harbored thoughts of a second potential presidential run when she arrived at the department. But aides say Kerry, a 69-year-old Vietnam veteran, is giving himself completely to a job that in many ways is the climax of his political career and the realization of a lifelong dream after years as chairman of the Senate Foreign Relations Committee. Now he wants to tackle head-on the world’s thorniest foreign policy conundrums.

Kerry, State Department spokeswoman Jen Psaki said, “believes this difficult moment in the world requires a willingness to address complicated issues. He believes the risk of high-stakes, personal diplomacy are far less than the risk of leaving difficult situations to fester or spiral out of control. That’s why he has invigorated our efforts in critical areas — such as North Korea, Syria and the Middle East peace process — and has personally invested time and effort to move the ball forward.”

No challenge may now be bigger than Syria, where a two-year civil war has killed at least 93,000 people.

Signaling a shift from the cautious approach of Obama’s first term, Kerry announced his first trip abroad would focus on changing Assad’s belief that he could prevail militarily and on pushing him into eventually relinquishing power. Since then, however, the fighting has only gotten worse. Thousands more have died as Assad firmed his grip over much of the country and the U.S. hasn’t even delivered all the nonlethal aid Kerry promised Syria’s rebels, let alone any of the weapons or ammunition that Obama recently authorized.

Having failed to reshape the war, Kerry changed strategy by going to Moscow to re-launch a peace process for Syria that Clinton engineered in June 2012 but had been all but forgotten in the months since. In Moscow, Kerry boasted that the former Cold War foes just accomplished “great things when the world needs it” by deciding to convene an international conference, perhaps by the end of May, that would include Syria’s government and opposition.

That conference has been delayed until at least July, and maybe August, and it might never come off at all given the opposition’s refusal to negotiate while it is losing land to Assad and getting so little help from the United States and other Western powers. That failure falls directly on Kerry, who as part of the U.S.-Russian approach was tasked with delivering the opposition to the bargaining table.

Russia may have lived up to its end of the bargain by guaranteeing the Assad government’s attendance at any future peace conference. But Putin and the Kremlin also have been undermining peace efforts by sending more weapons to help the Syrian government’s counteroffensive.

Kerry’s one-man diplomacy in Syria is in some ways emblematic of his tenure.

Officials say he opted to revive the U.S.-Russian strategy for a Syrian transitional government during his walk in the backyard of a Moscow guesthouse with Foreign Minister Sergey Lavrov, informing aides only after of his decision. Afterward, he insisted he wasn’t simply rewinding the clock by a year because the U.S. and Russia were now going to find ways to put the plan in place.

More than two months later, there has been no progress.

On Middle East peace, too, Kerry has put his credibility on the line.

Refusing to avoid one of the world’s most difficult conflicts, as Obama and Clinton largely did over the second two years of the first administration, Kerry has made four trips to the region to meet with Israeli Prime Minister Benjamin Netanyahu, Palestinian President Mahmoud Abbas and senior government members from both sides. Kerry will visit the region again this coming week to try to push the two sides back into talks, despite little to show so far for his efforts.

Kerry insists his quiet diplomacy is making headway, a claim that only he, Netanyahu and Abbas truly can substantiate because most of the discussions are one-on-one. Several senior Israeli and Palestinian officials have suggested otherwise in highly critical comments to local and international media. Few American officials, however, seem to know what is going on because they say Kerry rarely briefs even the most experienced U.S. negotiators in that part of the world on his talks.

At times, the process has seemed ad hoc.

In Jordan last month, Kerry announced a sketchy $4 billion economic revitalization strategy for the West Bank that would accompany his peace plan. No details were provided, and U.S. officials even sent reporters to aides of U.N. peace mediator Tony Blair for more information. Blair’s staff wouldn’t provide information or even confirm that the outline of an economic plan exists. Officials say Kerry’s friend, investor Tim Collins, is handling the portfolio, though it’s unclear if any money has been secured.

On Mideast peace, Kerry is largely fighting the battle alone. Since Obama’s visit to Israel in March, Kerry has gotten almost no public displays of support from the president, with the White House appearing reluctant to stake political capital in an endeavor that so often has proved a disappointment.

Some U.S. officials have scoffed at the notion that Kerry is getting anywhere, though they allow that the White House has given him until roughly September to produce a resumption of negotiations.

Ben Rhodes, Obama’s deputy national security adviser, praised Kerry’s efforts thus far.

“None of these are issues that you can solve in a few months,” Rhodes said. “The fact that he is taking these on with the energy he has is a great asset to the administration. These are the toughest challenges we have.”

Kerry’s individualist approach to foreign policy is partly a matter of circumstances and partly intentional.

With few Senate-confirmed senior officials in place at the State Department, Kerry has been short of aides at the highest level who might act as envoys to drive forward his agenda in his absence. Among others, Clinton had George Mitchell to push Mideast peace and Richard Holbrooke in Afghanistan and Pakistan. Kerry lacks any such high-profile figures at his side.

Those who’ve worked closely with Kerry say the approach also reflects the great stock he puts in his personal diplomacy and the belief, perhaps more widely shared in the rarified air of the Senate, that leaning on his close relationships with foreign leaders and dignitaries can deliver more results than delegating authority to capable bureaucrats.

That has left Kerry doing much of the work himself, from ordering up policy papers to envisioning new initiatives, while traveling the world or publicly regaling foreign ministers in Washington with stories of their past encounters or meals in exotic capitals.

Kerry makes it a point to stress the long-standing friendships he maintains all over the world. And his network of contacts may have played a role in the only tangible concession he has gained so far in the Middle East: a decision by Arab countries to sweeten their comprehensive offer to Israel for peace with the Palestinians.

The Arab League’s proposal now allows Israel to keep some of the land it conquered in the 1967 Mideast war on condition that Israel agrees to cede territory on its side to a future Palestine. Kerry hasn’t been able to announce any commensurate move from Netanyahu, who brushed the Arab terms aside.

Some U.S. officials wince at another legacy of Kerry’s Senate years: his penchant for loose or inaccurate talk.

On his very first day as secretary, he recounted his childhood bike rides in postwar Berlin past Adolf Hitler’s tomb. Hitler had no tomb. On more substantial issues of policy, he has made questionable claims over everything from U.S. drone policy to climate change.

At other times officials have questioned his restraint, such as when he lauded America’s emerging “special relationship” with communist China. For one of the United States’ principal geopolitical foes, Kerry was using a diplomatic term generally reserved for ironclad U.S. allies such as Britain and Israel.

He also seemingly ad-libbed unauthorized offers of a softened military posture to China and engagement to North Korea in a bid to calm tensions, which aides believe his engagement helped achieve.

On a trip to Turkey, he irritated advocates of Israel by appearing to compare the victims of the Boston Marathon bombing with the Turks killed in a 2010 Israeli commando operation on a ship trying to break Israel’s blockade of Gaza. Days later, in Brussels, he raised eyebrows by suggesting that one of the Boston Marathon bombing suspects became radicalized while on a trip to Russia, something investigators had not concluded.

For all his idiosyncratic style, Kerry has not dodged any diplomatic fight. He has even spoken privately of taking on Cyprus’ four-decade deadlock between ethnic Greeks in the south and Turkish Cypriots in the north. He sought to re-engage the U.S. with post-Hugo Chavez Venezuela on a trip to Guatemala this month, helping secure the release of an American filmmaker jailed for alleged espionage.

Officials say other governments Washington has long seen as rogues — from Cuba to Zimbabwe — could get a fresh look.

With no election around the corner and few worries about his image, Kerry has shown a willingness to think big.

Soon, however, he’ll have to produce.

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