Did you even read the article? The government is actively sifting through his mail, more than 10 years after he was considered to be a threat... and a hippy environmentalist threat at that...
There are environmentalists and there are arsonists. His organization was the latter.
And guess what: the government has to "sift through your mail" to deliver it. All they're doing with him is remembering what they saw. Because he belonged to an organization that burned shit down.
I feel this is what a lot of people forget -- or ignore -- when they come on HN to proselytize for this week's armchair activist crusade. 99% of the time, this shit is used to stop legitimately dangerous people. It's manned by people who aren't out to ruin your life; they just want to live theirs with as little shit to worry about as possible.
Reddit, HN, and the like are collectively patting themselves on the back and talking about revolution as though they're going to do anything other than click those little arrow icons next to posts. The third top comment here is talking about DDoSing the post office -- with absolutely no hint of irony. It's ridiculous.