President Biden personally thanked more than 100 members of the U.S. government earlier this month for their help in negotiating the recent prisoner exchange with Russia.

The massive deal brought Michigan native Paul Whelan back to the U.S after being held in Russia since the end of 2018 on charges of espionage that both he and federal officials say are bogus.

Some experts believe the exchange could set a model for how nations engage in such so-called “hostage diplomacy” in the future.

Northwestern University Assistant Professor Danielle Gilbert works with the Center for Strategic and International Studies (CSIS) on matters concerning wrongful detentions.

She says duplicating the kind of deal that gained Whelan’s release will not be easy.

Listen: Why the deal that freed Whelan, Gershkovich may be hard to duplicate

The following interview has been edited for clarity and length.

Danielle Gilbert: These are extremely difficult negotiations. Not only are we talking about some of the fiercest adversaries that have to come to the table to come to an agreement in terms of the United States and Russia; but also the challenge of bringing together all of these other parties, getting other governments to agree to put their own prisoners on the line to participate in this complex multi-party swap. This was extremely advanced negotiation that took place at the highest levels of government over the course of quite some time. And that all of it was held as such a tight secret until the actual release was also pretty spectacular.

Quinn Klinefelter, WDET News: There are reports that Germany wanted Putin opponent Alexei Navalny as part of any deal that would include Whelan in exchange for a Russian assassin that was held by Germany. And then Navalny passed away a few days after the deal was supposedly struck. Yet it seemed Germany’s willingness to make a deal continued and that seemed to open the pathway to the eventual exchange. Does it surprise you that Germany would actually, finally partake in such an effort?

DG: Vladimir Putin and his government continually pushed for the release of Vadim Krasikov, the FSB assassin who was imprisoned in Germany for murder. But the United States government didn’t have the power to release Krasikov, that was something that was only up to Chancellor Scholz and the government of Germany. So that took some really difficult conversations behind the scenes. President Biden was drawing on the friendship and the alliance with Germany, speaking to Chancellor Scholz and representatives at the highest level of the German government. And not only about the importance of their alliance, their partnership and friendship with the U.S. and opposition to what Russia was doing in this particular case, but also ensuring that the ultimate deal — the prisoner swap — included Russian dissidents, political opponents to Vladimir Putin. That those people would be released from detention and they’d be able to come to Germany. Countries like the United States and its Western democratic partners and allies are being targeted by autocratic states like Russia.

QK: Beyond the number of nations involved in the swap, the sheer multitude of prisoners involved in the exchange seems to be far different from what one would normally think of in a hostage deal, which is sterotypically a one-for-one prisoner swap. Do you think similar hostage deals that could happen in the future are also likely going to have to include many, many more countries and in effect “enlarge the pie” of what is being offered in any exchange?

DG: It’s a great question. It remains to be seen. I think in past prisoner swaps with Russia, we really have seen that one-for-one dynamic. Russia wrongfully detains an American and they demand the specific release of a Russian who was arrested in the United States. And those deals, while they might be controversial, are about as straightforward as they can get in terms of prisoner swaps. This one (involving Whelan) was extremely complicated because of the number of countries involved, the number of prisoners, the complicated choreography. In an ideal world, the countries that are frequent targets of this kind of attack are going to start really working together to deter the practice going forward.

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QK: One of the criticisms of the exchange has been that it rewards Russia and by extension any other country that would follow suit for taking Americans hostage that the government believes could be used as trade bait. How do you think the U.S. can combat that kind of approach?

DG: That requires coordination among allies, drawing on the tools of the international system. How can they punish a state like Russia for engaging in this practice? There might be sanctions on hostage takers, it might result in prosecution or other means of drawing on a country’s own legal system. And thinking about ways to exclude Russia from the things that it might enjoy in the international system.

QK: The U.S. is already involved in the conflict between Russia and Ukraine. There’s few other examples that would be testier for governments to be dealing with than an ongoing war. And yet this deal seems to have achieved Russia’s goals. So in the future would actions like sanctions be sufficient? Is there something else that countries can do to try to deter this type of hostage-taking?

DG: That’s the real million dollar question. It’s the question that gets me up in the morning. Government officials in the United States and a lot of other frequent targets, countries like Canada, the U.K. and Australia are putting their best minds to work to figure this out. The commission that I’m a part of at CSIS is also working on this question and hoping to make recommendations to the next U.S. presidential administration on how they might think about deterring this practice going forward. One big part of it has to do with prevention. Let’s say the U.S. government can’t put more sanctions on these countries that are already so heavily sanctioned. Well, what can the U.S. government do to prevent its citizens from traveling to places like Russia in the first place? How can they increase education? How can they engage the private sector that requires employees to travel to make sure that Americans who are going to these places are aware of the risks that they might be facing, understand other countries’ laws and hopefully stop traveling to places that the U.S. government strongly urges Americans not to visit, like Russia.

Use the media player above to listen to the interview with Danielle Gilbert.