Diane and John Foley, Paula and Ed Kassig, Marsha and Carl Mueller, and Shirley and Art Sotloff are parents whose children were abducted and killed by members of the Islamic State.

We are the parents of James Foley, Peter Kassig, Kayla Mueller and Steven Sotloff. As Syria’s civil war unfolded, our children saw the Syrian people’s suffering and wanted to help, whether by providing humanitarian aid or by telling the world about this disaster.

While carrying out this work, they were abducted by members of the Islamic State, also known as ISIS. They were starved, tortured and beaten. According to witnesses, Kayla was repeatedly raped by the then-leader of ISIS, Abu Bakr al-Baghdadi. Jim, Peter and Steven were publicly murdered in the most brutal way imaginable. Nearly six years later, their bodies haven’t been found. No one has faced justice for their murders.

Some of the men who allegedly committed these atrocities are now in U.S. military custody in the Middle East. We implore President Trump, Attorney General William P. Barr and the Justice Department to have the detainees brought to the United States to face trial.

Like any grieving relatives, we want to know the full truth about what happened to our loved ones, and we want to see our children’s murderers held accountable. These things can happen only if the suspects are put on trial before a jury in an American court of law.

Some of the ISIS members implicated in these crimes, including Mohammed Emwazi, also known as “Jihadi John,” and al-Baghdadi, are dead and beyond the reach of earthly justice. But others are being held, right now, on U.S. bases in the Middle East. The detainees include Alexanda Kotey and El Shafee Elsheikh, two of the surviving ISIS members referred to by their captives as “the Beatles.” They are British citizens who reportedly participated in the detention, torture and execution of American hostages.

With the U.S. military reducing its presence in the Middle East, we worry that the detainees will never face trial, just as hundreds of terrorists who were detained on U.S. bases during the Iraq War were let go as the United States withdrew its forces. Having escaped justice, many — including al-Baghdadi before his death — went on to form the Islamic State leadership.

Risking a repeat of this regrettable history is alarming enough. But detaining suspects indefinitely without trial is also bad policy. Terrorists use it as a recruiting tool and as an excuse for hostage-taking, accusing the United States of doing the same. Islamic State propaganda makes heroes of its members in U.S. custody, portraying them as living martyrs — a message that is repellent to the loved ones of their victims.

The U.S. government should send a more powerful message: It doesn’t matter who you are or where you are. If you harm American citizens, you will not escape. You will be hunted down. And when you are caught, you will face the full power of American law.

There is no nation on Earth better at bringing terrorists to justice than the United States. American laws are rigorous and comprehensive. Law enforcement and intelligence agencies are masters of their craft. And U.S. prosecutors have a long track record of success. More than 400 convicted terrorists are now securely behind bars in federal prisons, their crimes having been laid bare in open court.

We implore the Trump administration: Please, for the sake of truth, for the sake of justice, order these Islamic State suspects transferred to the United States to face trial.

In one of her final letters home, Kayla signed off, “With all my everything.” That is what Kayla, Jim, Peter and Steven are to us: our everything. Obtaining justice for them would mean the world.

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