Some people disagree with the opinions quoted above, 

saying that Problem X is the invention of overzealous 

news reporters who are trying to make a story out of 

unconnected incidents.  But if Problem X were only

a myth, would the government really fund expensive 

research projects or make such major policy decisions?

Brown says "Naysayers have come forward to try to thwart (11)

nearly every great social engineering project, from the 
 
New Deal to HMO reform, so it is no wonder that petty critics 

will raise their voices now" (34).

(11) Ad hominem.  Brown is merely calling his critics "naysayers" and "petty."  He is calling his opponents names instead of addressing the intellectual content of their argument.