Israel has a long history of unequal prisoner exchanges. Since 1982, it has released thousands of Lebanese and Palestinian prisoners in exchange for a handful of Israeli soldiers and civilians, some of them living, others already dead. Last week, it agreed to release more than a 1,000 Palestinians, many of them serving life sentences for murder, in exchange for Gilad Shalit, an Israeli soldier who has been held hostage in Gaza since June 2006.

The Jewish state's repeated willingness to pay an exorbitant price for its citizens...