James Foley's Siblings Say US Could Have Done More to Save Him

— -- The brother and sister of U.S. journalist James Foley, who was slain by Islamic terrorists, believe more could have been done to save their brother and said the U.S. should reconsider its approach in dealing with kidnappers.

Michael and Katie Foley spoke with Katie Couric in an exclusive interview on Yahoo! News.

James Foley, 40, was beheaded by the Islamic group ISIS, which is also known as ISIL. The group is now threatening to execute another captured American journalist Steven Sotloff. ISIS killed Foley and is threatening to kill Sotloff partly because of the U.S. air attacks on their forces in Iraq. The group had also been rebuffed when it demanded a $100 million ransom for Foley.

"I really, really hope that in some way Jim's death pushes us to take another look at our approach, our policy, to terrorists and hostage negotiations and rethink that," Michael Foley, 38, said. "Because if the United States is doing it one way and Europe is doing it another way, by definition it won't work."

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The U.S. does not negotiate with terrorists, but Europe has been known to pay for the release of prisoners.

“The U.S. could have done more on behalf of the western and American hostages over there and still... you know, dealt with the broader, worldwide issues. Other nations have done that. And that’s been a source of frustration for me,” Michael Foley told Couric.

“Take the money aside, there’s more that could have been done directly on Jim’s behalf and I really hope that with respect to Steven, they take some action quickly,” he said.

“There is things that can be done. We are sitting on prisoners for example in Guantanamo. It doesn’t have to be financial. There’s ways to do it... I just feel strongly that more can be done, moving forward,” Michael Foley said.

The terrorists sent the Foley family a letter in August stating their son would be killed.

"It was just chilling, it was full of so much hate," Michael Foley said.

"I don't even know how a human being can even have that fierce and intense hate for someone else," Katie Foley, 26, said. "I don't even understand where that type of hate comes from."

The siblings said it's possible James volunteered to die first.

"I have no doubt ... he's always been that way," Michael Foley said. "[He] truly cares more about others than himself. I think he was probably the strongest and most prepared for it. God forbid there's others. But you can see just from the clips, from the video, he wasn't afraid."

The heartbroken siblings, whose brother reported from the dangerous frontlines in the Middle East, also spoke about the day he was kidnapped in 2012.

Katie Foley, a nurse for the U.S. Navy, was the last person in their family to speak to James, through Skype on the morning of Thanksgiving, before she went to work.

"I told him, 'Happy Thanksgiving,'" she said. "And he's like, 'It's Thanksgiving over there?' And I said, 'Yes, it's Thanksgiving' ... we all love you. And then, I went off to work, and, obviously, we know the rest of the story."

They hope their brother will be remembered as a good friend, journalist and teacher.

"Jim was a hero," Michael Foley said. "He was my hero."