Much of what makes Israel unique needs to be understood to explain the grisly prisoner exchange that took place last week.

Israel freed a child-murderer and four prisoners of war, along with about 200 bodies of assorted terrorists and infiltrators, for coffins bearing the remains of two Israel Defense Forces reservists, Ehud Goldwasser and Eldad Regev.

That asymmetrical trade is not easy to explain abroad. The Foreign Ministry and the IDF are saying the swap highlights the difference in values between Israel and Hezbollah: Lebanon and Hezbollah are elevating Samir Kuntar, a man who crushed the skull of a 4-year-old girl, to rock star status; Lebanese must determine whether the destruction Hezbollah brought upon the country to free Kuntar was worth it.

Those make good sound bites. But why Israel went through with the deal cannot be explained in a 30-second segment, because the reason has to do with the next war, and with what is going in the minds of parents and officers who send their charges to war. It also has to do with lessons from the Holocaust.

No other country in the world would have made such a deal, critics of the exchange have said. And they are right. But no other country in the world bears the scars that Israel does, nor the almost absolute knowledge that there will be other wars to fight in this generation, other sacrifices to be made.

The swap brings closure to the Goldwasser and Regev families. It brings closure to the Second Lebanon War, which was launched to bring the captives home.

But it in no way brings closure to Israel’s battle with Hezbollah. It is not as if now that this chapter is over, Israel and Hezbollah will develop better relations. Hezbollah will not cease its hostile acts against Israel now that their hero Kuntar is back on Lebanese soil, nor will they stop if the Shebaa Farms issue is settled.

If all those issues were put to rest, there would always be the issue of the seven villages in the Galilee that Lebanon claims. And were that problem eventually solved, another one would crop up as Hezbollah continues to push back the goalposts. No, there is no closure with Hezbollah, just preparation for the next confrontation.

It is in the preparations that the swap comes into play. It has become almost a cliché to say that each soldier must know when he goes into battle, the country will do everything in its power to bring him home if something untoward occurs.

But forget the soldiers — they are not thinking in these terms. Most of the soldiers still live with their youthful sense of invincibility. They are busy training and fighting and will not be any more or less motivated to do so by this deal.

That promise matters among the officers. The officers need the trust of their soldiers. They need to know that when they head into battle, their soldiers will follow. And for that they need their soldiers’ trust.

For generations the officers have said the IDF leaves no soldier behind, dead or alive. And until that credo is changed, the officers need to know that these are not just empty words. This is what they tell their soldiers, and it is essential for future confrontations that their soldiers believe them.

Which explains why Chief of General Staff Gabi Ashkenazi was such a fierce advocate of the deal, even though he knows the risk this may pose for future soldiers. Ashkenazi needs the trust of those he commands.

When the Cabinet voted to approve the guidelines of the deal, the ministers knew that Israel would be trading for two bodies. Yet they voted for it. It is precisely here that the traumas of the collective memory of the Holocaust come into play.

Because of the Holocaust, Israel will always feel a sense of communal obligation . Whenever Jews are in danger, everything, must be done to try to save them, if only because so little was done back then.

Does this mean that Israel pushed the deal forward because of a sense of guilt over the Holocaust? Obviously not. But the trauma of the Holocaust is etched into the country’s collective subconscious, and does impact decisions.

Israel is a land of hundreds of thousands of Holocaust survivors, and their experiences shape how the nation looks at the world. Among these survivors are tens of thousands of people who will never know where their murdered family members were buried.

Is this the reason Israel went ahead with the deal? Again, obviously not. But it is part of the Israeli psyche, part of the reason Israel would do something that seems unfathomable to many who don’t live among us.

Herb Keinon writes for the Jerusalem Post, where this piece previously appeared.