Welcome to Hard Talk from the BBC World Service with me, Stephen Sacker.

My guest in this interview recorded on the 5th of March has just left a job which presented

him with potentially life-changing dilemmas on a daily basis.

For almost five years, Roger Carstens, a former elite soldier and State Department official, was America's

special presidential envoy for hostage affairs. His task was to engineer the release of U.S.

citizens held hostage or wrongfully imprisoned in hostile territory. He was appointed by Donald

Trump in his first term, and unusually he was kept on by

Joe Biden throughout his presidency. His tenure came to an end with Trump's return to the White House

in January. By then, he had secured the release of more than 50 Americans from a host of hostile

countries, including Venezuela, Iran, and most notably Russia.

From his first day in the job to his last, much of Carston's focus was on the families of those

in captivity. He reached out to them, communicated constantly with them, and tried to show them that

America was prioritizing the freedom of their loved ones.

But of course, every release came with a price.

And some of the deals Carston's engineered, particularly with Russia and Iran, prompted critics

to argue America risked being seen as rewarding the hostage takers in a way that would

encourage more of the same.

Carston's job is now done, but the debate goes on.

What is the liberty of one captive individual worth?

Roger Carstons joins me now on the line from Washington.

Welcome to Hard Talk.

Thanks, Stephen. Appreciate it.

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