The major problem that I have with it is that your time line is marked by black lines of varying length on the graph itself. This leads to the assumption on the part of the reader that the lines' lengths have some quantitative meaning. It takes further reading to realize they don't. Second, if you're trying to make a point, you need some kind of correlated data displayed. You don't seem to be showing, or attempting to show, a correlation between an action of the government of Israel (or another state) and a resultant spike or reduction in terror deaths. Perhaps a better way to display the data would be as percent change in deaths from terror in the six months following a new security measure as compared to the six months before. That way you might be able to display a trend (or lack thereof) to your audience. Right now it doesn't convince me of anything, especially not concisely.