Tim Kaine and Michael Pence surprisingly agreed on establishing “safe zones” in Syria for beleaguered civilians. But both candidates failed to mention the troop commitment such zones would take to defend.

In his 2013 assessment given to Congress, then-Joint Chiefs of Staff Martin Dempsey said that “thousands of U.S. ground forces would be needed, even if positioned outside Syria, to support those physically defending the zones. A limited no-fly zone coupled with U.S. ground forces would push the costs over one billion dollars per month.”

In February, Secretary of State John Kerry told a Senate panel that the Pentagon has estimated it would take between 15,000 and 30,000 American troops to secure safe zones within Syria.