Before I get to Kerry's approach, let me remind my readers why any of this matters. Despite early White House expectations that Assad would fall, the Syrian struggle is now mired in a bloody stalemate in which more than 70,000 people have died and a country is being pulverized. Barring a new approach, neither side is likely to triumph in the foreseeable future.
"The more probable outcome," according to the astute Syrian opposition activist Amr Al-Azm, "is the collapse and fragmentation of the state," and possibly a sectarian genocide. The blowback could affect Turkey, Lebanon, Iraq, Jordan, and Israel.
A failed Syrian state also would provide a power vacuum into which outside jihadis could flow, permitting them to radicalize local Islamists and obtain dangerous weapons from captured regime arsenals. And once a state collapses - as we know from the Iraq experience - it is very difficult to rebuild.
Back to Kerry. He understands this danger and warned last week about an "implosion" of the Syrian state.
Kerry also understands why Assad won't budge. "He thinks he's winning and the opposition is losing," Kerry said at his confirmation hearing. "We need to change Bashar al-Assad's calculation," he added.
Indeed, backed and armed by Russia and Iran, and aware that Washington won't give crucial antitank or antiaircraft weapons to the rebels, Assad seems confident that his regime can survive the fighting. So does Moscow.
While the rebels have managed to take control of some rural areas, no city has fallen yet. "In Bashar's calculus, he just needs to weather the storm," Azm told me. "And he's not necessarily wrong."
Kerry, however, believes he can change Assad's "current perception," facilitating talks between Assad and the rebels that could offer the president a comfy exile and provide protection for his Alawite (Shiite) sect. The secretary also hopes to find more "common ground" on Syria with Moscow, despite failed administration efforts in the past.
There are no signs that Moscow is receptive. Three days after Kerry placed a phone call to Russian Foreign Minister Sergei Lavrov on Tuesday, it hadn't been returned. Also last week, the Assad regime brushed aside opposition leader Moaz al-Khatib's offer to engage in talks. Clearly Assad does not feel a need to compromise yet.
So how to change Assad's "calculus"? "In order for the regime to negotiate, you have to degrade it," Azm said. He believes the United States would have to provide more visible support to the Syrian opposition, including funds for a new civilian opposition council and arms to a new, non-jihadist opposition military council.
As we now know, former Secretary of State Hillary Rodham Clinton and former CIA chief David Petraeus recommended a plan last summer to vet and train certain rebel groups and fighters. The agency apparently believed it had enough knowledge about rebel leaders to take such a step. Secretary of Defense Leon Panetta and the chairman of the Joint Chiefs, Gen. Martin Dempsey, supported the Clinton-Petraeus plan.
However, President Obama overruled his national security team. And since his reelection, he has made very clear his reluctance to consider any deeper involvement with Syria beyond increased humanitarian aid.
On a C-17 military transport plane returning from Kabul last week, I asked Dempsey about the thinking that went into his positive response to the idea of arming the rebels. "At the conceptual level," he said, "I thought if there were a way to resolve the military situation more quickly," it might prevent the collapse of Syria's institutions. "A failed state," he said, "is defined by the collapse of its institutions."
Dempsey stressed that "there were enormous complexities involved that we still had to resolve." Those included identifying which opposition leaders would commit to representative government and preservation of state institutions. "I wouldn't say to my satisfaction we ever reached a point I would describe as clarity," Dempsey said. "I think that continues to be a work in progress."
Yet Kerry embarks on his mission with few tools to prevent a failed Syrian state.
Syrian activists have repeatedly put forth plans for identifying and vetting moderate military opposition leaders, and monitoring the delivery of antiaircraft and antitank weapons. This would offset the plentiful weapons flowing from the Arab Gulf to jihadi groups that empower them to lead the fighting, and might enable the opposition to break the military stalemate.
Last spring, Kerry talked of arming the rebels. Now, instead of charting a new strategy, he seems limited to repeating past (failed) efforts, urging Moscow to help him ease Assad into exile. Meantime, the regime's planes bomb cities and towns into rubble, and the Syrian state rapidly collapses. The longer this goes on, the worse the outcome will be.
"To my knowledge no options have been entirely taken off the table," Dempsey told journalists on the plane. However, there are no signs that Obama will reconsider the option of breaking the Syrian military stalemate. This means Assad will hunker down as Syria implodes.
Trudy Rubin can be reached at email@example.com.