SENIOR OBAMA administration officials offered a stark and even frightening picture of developments in Syria in testimony to Congress on Thursday. March, they said, was the deadliest month yet for that country’s civil war, with more than 6,000 people killed; almost one-quarter of Syria’s 22 million people have been driven from their homes. “What started out as a peaceful demand for dignity and freedom,” said Acting Assistant Secretary of State A. Elizabeth Jones, “has become one of the most devastating conflicts of the 21st century.”

Worse, the intelligence community’s assessment is that the war will not end even if the regime of Bashar al-Assad falls. “The most likely scenario,” said Director of National Intelligence James R. Clapper Jr., is that for “at least a year, a year and a half, there would be continued inter-sectoral competition and fighting.” It will matter greatly who wins, since, as Robert S. Ford, the U.S. ambassador to Syria, put it, “there is a real competition under way now between extremists and moderates.”

Among the extremists is Jabhat al-Nusra, a branch of al-Qaeda that last week publicly swore allegiance to Osama bin Laden’s successor, Ayman Zawahiri, and said it would operate under a united leadership with al-Qaeda in Iraq. The group already controls towns and vital infrastructure in northeastern Syria; Mr. Clapper said it is operating in 13 of Syria’s 14 provinces and “punching above its weight.” And those aren’t the only extremists: On the regime’s side, Mr. Ford said, are Shiite militia fighters from Iran, Iraq and Lebanon’s Hezbollah movement.

CIA Director John O. Brennan summed it up: “I’m concerned about this fracturing of the country that is allowing certain groups such as al-Nusra to gain strength, because they have agendas inside of Syria and potentially outside that I think are contrary to U.S. national security interests.” Among the gravest threats is that al-Qaeda or Hezbollah will gain control over Syria’s large arsenal of deadly chemical and biological weapons.

So what is the administration’s plan for defending American interests? There, the officials’ testimony was as muddled and contradictory as their description of the situation was clear. Mr. Ford said that the administration was still banking on “a negotiated political transition,” in which Mr. Assad voluntarily steps down. But as Mr. Clapper said, the intelligence community foresees the “most likely scenario” as a messy fight among factions, not a brokered handover. Of Mr. Assad, Mr. Clapper said: “His own perspective is that he believes he’s got the upper hand. . . . He’s also said he was born in Syria and he’s going to die there.” In other words, the negotiated political transition is a fantasy.

Mr. Ford said that “we need to weigh in on behalf of those who promote freedom and tolerance.” Yet Ms. Jones reiterated that the administration was opposed to providing “lethal support” to any Syrian forces — notwithstanding the weapons and fighters that Mr. Ford said were being supplied by Iran or the growing military capability of al-Qaeda described by Mr. Clapper. Translation: It’s vital that Syria’s moderate forces win, but we won’t counter the military support the extremists are getting.

Senators from both parties expressed exasperation with this non-policy, but not as much exasperation as President Obama’s stubborn passivity deserves. Mr. Clapper was asked whether the United States and its allies were prepared to secure Syria’s chemical weapons sites. His answer, that it “would be very, very situationally dependent,” was anything but reassuring.