On the path to defeat?

WASHINGTON — The threat to the U.S. from global jihadist groups has escalated in the past three years, with the number of groups increasing by more than 50% and the estimated number of militants doubling, according to a report to be released on Thursday.

The report by the Rand Corp. think tank, which used public data to take a kind of global census of al Qaeda and related groups, will say the civil war in Syria has been the largest driver of the growth of jihadist activity. Syria is the location that has seen the greatest growth in number of groups and numbers of militants, which now make up more than half of the number of al Qaeda-sympathizing jihadists world-wide.

“It’s become a breeding ground for jihadist activity,” said the report’s author, Seth Jones, associate director of Rand’s International Security and Defense Policy Center.

In the past few months, militants there have shown growing interest in tapping Western resources and mounting attacks outside Syria, he said, noting last week’s suicide attack by an American in Syria, in addition to recent arrests of alleged Syrian-trained fighters in France and Spain, as well as one allegedly involved in a deadly shooting last month in Belgium.

The Rand findings also cast doubt on the Obama administration’s efforts to end the U.S. military presence in Afghanistan by 2016 and keep Syria at arm’s length. A complete withdrawal from Afghanistan, the report said, “could seriously jeopardize U.S. security interests,” because of the continuing terrorist presence in Afghanistan and Pakistan. It also calls for a “more aggressive strategy” in Syria, either clandestinely or working with locals.

National Security Council spokeswoman Caitlin Hayden said she couldn’t comment on a report that hadn’t been released, but referred to President Barack Obama’s speech last week where he announced ramped-up partnerships with local allies. In that speech, Mr. Obama also said “U.S. military action cannot be the only—or even primary—component of our leadership in every instance.”