When the Israeli government exchanged over 1000 captured terrorists for captured Israeli soldier Gilad Shalit last fall, I pointed out that the deal was likely to cost a lot more innocent lives than it saved, because many of the freed terrorists are likely to go back to their old ways. Sure enough at least two of them have already done just that . And they are apparently not the first Shalit exchangees to have done so. Given that there are 1000 more where these two came from, this is likely to be just the tip of the iceberg.
As I explained in my original post on this subject, the likelihood that freed terrorists will commit further atrocities is just one of several grave flaws with these types of deals. They also incentivize future terrorism and hostage taking by showing the terrorists that such tactics work. In addition, endangering innocent civilians in order to save a captured soldier who volunteered for combat duty is a wrongheaded inversion of moral priorities. Still, the high likelihood of recidivism by released terrorists is a sufficiently grave risk that it by itself outweighs any possible benefits of such deals, especially if the ratio of released terrorists to freed prisoners is so absurdly lopsided that it becomes nearly certain that the exchange will cause more harm to innocent people than it prevents.
This conclusion is inescapable on utilitarian consequentialist grounds. But it is also compelling in terms of theories of natural rights. After all, every time the freed terrorists kill or injure innocent civilians, they violate their victims’ rights to life, liberty, or bodily integrity. And the release is likely to cause far more such rights violations than it prevents.