Can someone explain how 9/11 deniers damage america?

[j2k4]

You are quite correct, but the fact is that a certain percentage of the population will always be susceptible to conspiracy-thought, and this is, as such, the norm.

The media suffers this malady in similar proportion.

so what you're saying is conspiracies don't exist?

How do you gather that?

Of course they exist, but in wee tiny numbers that have need of such a word; they don't lurk around every bloody corner like you think.