The hyperbole keeps the focus off the more important, debilitating problems. Further, it makes you sound shrill and makes people (IMHO) not want to read another word. I'll put it this way: let's take your second list, combine it with "the single, worst thing to happen in recent memory", and add a couple others I have seen complaints about.
While NCLB may be bad, it probably would not make many serious reformers top 10, much less top 5. Technically, it may have followed these others chronologically, but calling it "single" and "worst" is hyperbole. If I had not called you on it, your second, more measured post would probably not been written.
The piece of recent government legislation which has had the worst effect on public schools is the NCLB act.
Is the NCLB act the only factor which contributes to the continuing downward spiral of public schools? Of course it isn't. It is, however, the ONLY one which is a federal mandate. If you want to see the complete and utter breakdown of the public school system, envision what would happen if our government were to federalize solutions to the other factors you cited. Liberal indoctrination, powerful unions, the breakdown of traditional families...these are all factors which are effecting our schools, that is not a dispute. Those factors can be addressed and even controlled at a local or state level. The NCLB is the worst because it is federal.