It's a difficult one. I understand the reasoning for going in relation to "not letting the terrorists win". On the other hand, if you don't feel safe, then it spoils the trip. I visited Qatar not long after the first Gulf War, as my dad and his wife were working and living over there. For all the conflict seemed to have died down, I did feel a little edgy, and a visit to the very north of the penninsula brought about a very real reminder of what happened - remember the oil terminals that were set alight? The coastline of Qatar was still covered in the oil slicks and the devastation was horrible. Also, (although not a Middle Eastern country) I visited Zimbabwe in 1991 and I loved that place so much. The people were so friendly, beautiful and proud of their country. I vowed to visit again, but at the moment, there is no way I would take the risk.
I think it's all down to how comfortable you would feel making a trip to such an area. As for waiting for for things to settle down a bit, you could be waiting a very long time, so if you feel so strongly about it, maybe you should grasp the nettle and make the trip?