Haaretz reports the letter by chairman of the Joint Chiefs of Staff, Gen. Martin E. Dempsey outlining options to assist Syrian rebels could costs billions of dollars.

“In Dempsey’s letter, he enumerates that training and assisting opposition forces alone could cost up to $500 million a year. An offensive that includes limited long-range strikes could cost billions of dollars over time, and the enforcement of a no-fly zone, that require “shooting down government warplanes and destroying airfields and hangars” could reach $1 billion a month.”