A woman and child walk past the ruins of a restaurant where four Americans were killed in a suicide bombing in January in Manbij, Syria. One of the four killed was a Syrian American immigrant who served as a linguist for U.S. intelligence members. (Delil Souleiman/AFP/Getty Images)

Last month, U.S.-backed Syrian Democratic Forces captured Islamic State fighters believed to be responsible for the January suicide attack that killed four American intelligence personnel in Manbij, Syria.

One of the Americans killed in that attack, Ghadir Taher, was a Syrian American linguist supporting the team’s sensitive intelligence mission. She was a Defense Department contractor, a Syrian immigrant and naturalized U.S. citizen from East Point, Ga., who volunteered to deploy to combat in Syria with the U.S. military. Her loss is a tragic reminder of the crucial role immigrants play in U.S. national security, an important warning that the U.S. intelligence community is dependent on immigration for language and cultural skills that protect American lives.

As Americans consider the future of immigration policy, we should think about immigration as consistent not only with our values but also with our safety. The military, intelligence and law enforcement communities often stop terrorists because immigrants are on the front lines helping to identify those who wish us ill. The most sensitive and dangerous interpreter jobs with our Special Operations and general-purpose military forces, law enforcement elements and intelligence agencies require high-level security clearances, which normally require U.S. citizenship.

By and large, only immigrants can deliver true native language ability and deep cultural understanding. Those with such skills have been in high demand in recent decades. Many have left normal American lives to answer the call. They often have deployed to the world’s most dangerous war zones to serve as contractors alongside U.S. troops and intelligence officers. And a number of them have been killed or wounded.

As the examination of our immigration policies continues, we should not forget those Americans who have volunteered to serve alongside those in uniform, law enforcement and our intelligence agencies. There have been many unsung heroes in the wars of the post-9/11 period, and our linguists have been among them.

David Petraeus, Washington

David Petraeus commanded U.S. and coalition forces in Iraq and Afghanistan and was director of the CIA.

Phil Caruso, Washington

Phil Caruso deployed twice to Afghanistan as a case officer conducting intelligence operations.