We have negotiated with terrorists before - whether through "back channels" or out in the public, but its been done. Back in 2007 we negotiated with Sunni insurgent leaders in Iraq to get them to stop bombing US troops and join the fight against al-Qaeda in Iraq. We bribed them. We paid them off. And if you Google the statements of various US officials back in 2005-2006, they were insulted when the US media referred to the Sunnis as insurgents. No, those officials insisted, they’re terrorists!

We also have negotiated in the past with the Taliban in Afghanistan as well. Cutting peace deals with different leaders of various provinces in exchange for money/protection, etc. Ronald Reagan's talks with Iran aimed at winning the release of U.S. hostages held in Lebanon - is also another example.

I dont condone negotiating with terrorists, but sometimes opportunities are presented that should be discussed in a negotiation. Prisoner exchanges, etc. Israel has done it with Hamas, British with the IRA, Spain with the Basque. The Taliban apparently has had one of our troops as a hostage for a few years, I think we owe it to his family to see if their is something constructive we can do to get him back alive.

Despite grand declarations, in practice, most democratic governments—even the U.S. and Israel, both known for their uncompromising stance on the matter—negotiate with terrorists. An argument could be made for Israel, a country which has perhaps more experience than any other with terrorism, negotiating with Hamas. Sometimes a government might make a judgment call that the benefits of negotiating with terrorists surpass the costs. Each case is different.

Just my two cents.