You've probably seen something about the Protect IP and Stop Internet Piracy acts, but, in case you, like me, don't want to blindly support something you haven't read about (but you also don't want to sift through information to get to the heart of the issue) the core issue is as follows:
The stated intention of both acts is to cut down on internet piracy and protect intellectual property theft (which is something I believe in for the most part: being in the arts, I wholly respect the importance of intellectual property).
However(!), the acts are overly vague and essentially circumvent the process of law, which would make it so the burden of proof is on the accused rather than the accuser (i.e. "Guilty until proven innocent," instead of the more common "Innocent until proven guilty").
While there is certainly a problem with internet piracy, these acts, at best ill-defined and at worst an attack on privacy, free speech, and law, are not the solution.
I've written to my representatives, and encourage you to do so, too.
Alternatively (or supplementarily), Google has one of the more convenient petitions on the matter, which is a fast way to contribute to the cause.