It is said that common foes build strong partnerships. Long before the terrorist army of the Islamic State of Iraq and al-Sham marched into the Iraqi city of Mosul, threatened to exterminate the Yazidis and Christians in Iraq, and attacked the country's Kurds, the Syrian Opposition and the Free Syrian Army were battling ISIS and pushing back this common threat to our people.

Now more than ever, there is a national-security impetus for the United States to support and arm the Syrian opposition to halt and defeat the ISIS campaign....