The end came quickly for one of the costliest covert action programs in the history of the C.I.A.
During a White House briefing early last month, the C.I.A. director, Mike Pompeo, recommended to President Trump that he shut down a four-year-old effort to arm and train Syrian rebels. The president swiftly ended the program.
The rebel army was by then a shell, hollowed out by more than a year of bombing by Russian planes and confined to ever-shrinking patches of Syriathat government troops had not reconquered. Critics in Congress had complained for years about the costs — more than $1 billion over the life of the program — and reports that some of the C.I.A.-supplied weapons had ended up in the hands of a rebel group tied to Al Qaeda further sapped political support for the program.
While critics of Mr. Trump have argued that he ended the program to curry favor with President Vladimir V. Putin of Russia, there were in fact dim views of the effort in both the Trump and Obama White Houses — a rare confluence of opinion on national security policy.