Update 2013-08-05: Nope! I was wrong, wrong, wrong. The PRISM data is being shared with drug enforcement agencies to build cases, and then the origin of the data is being concealed by the DEA because they know they're not supposed to have it. This is pure abuse of the surveillance powers they've given themselves for a purpose totally unrelated to national security. I retract my position below: shut it down.
I continue to believe we are paying way too much attention to PRISM, and that PRISM is not that big a deal, and the government can keep doing it if it wants to, though I don't believe it's particularly effective. This has not been a popular stance.
So by way of counter-argument, here are some things I do think are a big deal, and are genuine threats to our democracy. You may or may not consider it a cop-out that the first two are related to PRISM, but I don't think so. I don't like PRISM, I just don't think it's important.
These are in no order other than that in which I thought of them; they are especially not in order of importance.
- The persecution of whistleblowers (particularly Bradley Manning, but also Snowden himself, even though I don't think he blew the whistle on anything we hadn't already found out)
- National Security Letters and their built-in gag order, source of much unnecessary secrecy (I don't care about PRISM, but it's damaging that it and other requests can be kept secret)
- The destruction of the Voting Rights Act
- Partisan redistricting that has given the Republicans a near-permanent majority in the house, and pushed them even further to the right
- Corporate personhood, and their ability to spend unlimited amounts of money on political campaigns, especially by corporations in the financial sector
- SuperPACs and their likewise unrestrained spending
- Ongoing attempts to nullify Roe vs Wade and effectively rob women of their right to choose
- The continuing enshrinement of unequal treatment of homosexuals before the law in the constitutions of many US states
This list also excludes major political issues (such as tax law, and immigration) that are not related to civil liberties but I also think are more important than PRISM.