That is just wrong. 4,325 killed as of last month.
Prevent? Do you have any evidence of that? The only evidence I know of is that Al Qaeda only attacks (domestically) about once every 8 years, since they started in 1993. As far as I know there is no publically available evidence that attacks were prevented post-9/11, only that no attacks occurred. Perhaps none were attempted? Or was Bush simply as good as Clinton at preventing attacks (they both suffered one each)? Perhaps Clinton prevented just as many attacks that are hidden in the classified record, just as Bush/Cheney have suggested their "preventions" are.
I dunno, if I was President, and I had prevented attacks, I'd kinda want everybody to know about it, I'd want pictures of the body bags or the captured terrorists on every news outlet.