What about the McCarthy era in the 1960s? Suppose we had a repeat of that in 2030, and the US wanted to purge everyone who believed in some "bad" ideology, sum

What about the McCarthy era in the 1960s? Suppose we had a repeat of that in 2030, and the US wanted to purge everyone who believed in some "bad" ideology, summarized by a single word, like "communism", except which we can't hope to predict now. Imagine further that this purge is being enforced by halfwits who don't actually understand the ideology in question, who get wrapped up in their own hysteria, and who are looking for any excuse to burn witches at the stake. And finally, imagine that said halfwits have an indexed, fully searchable database of all the Facebook statuses you've ever posted, all the Google searches you've ever made, and all the e-mails you've ever sent. Scared yet?