I posted a a post about how I felt about the Israeli and Palestinian conflict tonight. It just disappeared from my wall. How come?
Posts on my Facebook Page disappear and reappear.
There are many possible reasons, but if your post was seen as offensive by some viewers (and at the moment, posts on the subject are likely to inflame sentiments on one side or the other), they may have complained to Facebook and had your post removed.
I suggest you contact Facebook directly because none of us will really be able to tell you what happened.
We don't know if it was really posted or e.g. an error occurred. It may have been rejected by the automatic filtering of Facebook. Someone may have reported it to Facebook and it was removed duo to being in violation with the terms.