With Israel preparing for a major offensive, it must contemplate the risks a ground campaign will pose to the lives of those hostages. After four days of sweeping airstrikes on Gaza, Hamas is already threatening to kill a hostage every time Israel bombs a civilian Palestinian home without warning. And Gaza is a small, densely packed strip of land where the hostages invariably will be put in harm’s way by an invasion.

We spoke to Costa this week about how Israel is likely thinking about this dilemma and what a resolution could look like.

The following has been edited for length and clarity.

Calder McHugh: What details are Israel’s top intelligence officials scrambling to figure out right now?

Christopher Costa: What’s likely happening right now is Israel is trying to develop intelligence to identify the locations of where hostages are being held. So at the highest levels of the Israeli government, they’re laying out their intelligence and asking: Do we have anything that’s predictable, continuous and thorough on where the hostages are being held?

There is no plan for a rescue until you can identify where the hostages are. And I will say that this problem that the Israelis are dealing with is not like the Iranians holding Americans in one location in 1979. In that case, the United States was able to put together a rescue because all the hostages were held in one place. My conjecture is that’s not what Hamas would do — they would not consolidate hostages in one location. They would put them all over Gaza in different locations, probably underground.

McHugh: Hamas is threatening to kill a hostage every time Gaza is attacked by the Israeli military without warning. How does that affect the Israeli government’s response?

Costa: I don’t think Israel has ever been in this position. This is so immense, that at the end of the day, Israel is going to have to make some tough calls. And there may be hostages that are killed, although Hamas doesn’t have a long track record of killing hostages. It’s just a tough, tough problem.

Another difficulty is that one of the forces that would do the rescue — the YAMAM [Israel’s National Counter Terror Unit] just took on significant casualties; multiple individuals have sadly been killed in the initial battles that played out in the first 24 hours. So it’s going to be a tough problem. I think the United States moving a carrier in the region provides some deterrence, but mostly that deterrence, I think, is directed at Iran, even though that hasn’t been explicit.

I should say all of this is right out of the Iranian playbook. They were the ones that started exploiting hostages in Beirut in the 1970s and 80s.

McHugh: What happens if hostages start to be publicly killed?

Costa: When you start showing videos, hypothetically, of Israelis being killed as a reprisal for an Israeli strike that didn’t meet some kind of criteria, that Hamas was unaware of the strike or they were unable to move people (regardless, they’re not going to be honest brokers), then there’s going to be more pressure on the government. In a similar way, there was pressure on the United States to act when ISIS started beheading Americans in orange jumpsuits. It’s an emotional issue and passions are going to be unleashed on all sides of this fight by Israelis as well as Palestinians. Unbridled passion.

So I don’t know how this is going to end. But I do know that it poses the ultimate strategic dilemma for Israel. I will say, there is hope that there are brokers in the region that can start to have communications with Hamas, like the Qatari government — they have a relationship, they can start talking to Hamas. Those aren’t going to be direct Israeli talks. But they certainly have a track record of de-escalating problems in the region, and they brokered with Afghanistan. So there is some diplomatic outreach that could play out, but the Israelis have to consider diplomatic, intelligence, military rescue responses, and they have to worry about the long-term and the calculus of Iran as well. All of that has to be factored into the decision-making.

McHugh: Can you think of any comparable situation — in terms of scale or scope of hostage-taking — in recent decades?

Costa: I don’t think there is an equivalency. But Boko Haram, for example, will go into a village and go to a girls’ school and take 70 to 100 people. The Western press doesn’t really cover that in detail, but those kinds of things have happened. Hostages are taken into the hinterland and held as bargaining chips against governments in West Africa. So that’s one example that I can think of. And then we go back to the 1970s, when the United States had individuals held by a malign nation, Iran, in the midst of a revolution. But I don’t think we’ve ever seen anything like the convergence of all these lines that are happening today.

That’s the idea of Iran, the threat of Hezbollah in the north and Israel under pressure to do something dramatic, and they have declared war. This is not an operation, this is a declaration of war. That’s going to slow the economy down while Israel galvanizes all of its national resources.

McHugh: How long will it take Israel’s government to get a more accurate count of the hostages?

Costa: It’s hard to say, it’s hard for me to even conjecture. I think Israel is doing the math. And that might sound insensitive. But they’re doing the math based on witnesses that survived and identifying the bodies and interviewing witnesses. So I would say, in the next couple weeks, if not quicker than that, there will be a better accounting.

McHugh: And once it has that accounting, what will Israel do? What should it do?

Costa: It is a small nation. People are one or two people removed from the tragedy. I spoke to someone that lost a niece just this morning. So, if there are individuals that are killed and videos are posted, there’s going to be a demand to maybe slow down and calm the passions of the moment. The other problem we have is, if Israel moved into Gaza, that’s exactly what Hamas wants. That’s certainly what Iran wants.

Israel has had their challenges with counterinsurgency, in particular in Lebanon. Think about the casualties that could play out on the ground in Gaza. And then think about the converse of all of a sudden, videos of other civilians: Palestinian innocents and children dying. So, many countries in the world are going to suggest caution and restraint.

The lessons that I would share with Israel, if they would listen to me, is they have to prepare for a long war, which means not taking their eyes off Iran. But they do have to kill and capture as many Hamas as they can, just like the U.S. did with al Qaeda. And I think the enemy stands to circumvent some of Israel’s strength if Israel does do a full-fledged invasion on the ground in Gaza, where Israel doesn’t have a lot of room to maneuver.

So they’re gonna lose troops there. At the same time, I caution that Israel has to act proportionally. But what’s a proportional response to this? This is where I’m wading into Israeli politics, so I’ll be really careful here, but I’ll just say that Israel has to unify their nation somehow, because polarization just like it is in the United States is a crucial strategic vulnerability.

McHugh: Is hostage-taking an effective strategy for Hamas?

Cost: I think it is. And it’s just another tool in the toolbox, like indiscriminate killing of civilians is as cold as that sounds. From a terrorism calculus, hostages give them some leverage. If you put Israel in a lose-lose situation, where does that put Hamas? They took hostages, but if the Israelis killed them in strikes, Israel looks like the bad guy.

McHugh: What will the coming days and weeks and months look like on the ground?

Costa: I want to see the West Bank stay stable. I want to see the Palestinian Authority step up. I want to caution Israeli settlers in the West Bank to remain calm. Terrorists want to cause an overreaction. Passions have come unleashed. So what I want to see is a proportional response, that destroys Hamas leadership and rank and file to the extent they can, just like the U.S. went after al Qaeda. And yet, I want to see a limited response so that civilians, to the extent that they can be protected, can be protected. The problem is, Hamas will hide among civilians.

The worst case scenario is Iran and Syria get involved more directly, or Hezbollah in the north. That’s what I’m very concerned with. But I think there are possibilities in the next 30, 60, 90 days, where this can be de-escalated. A lot depends on what Iran does. A lot depends on what happens in the north. I think this is likely going to be a protracted conflict over months, not weeks. That’s only my calculus.

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