This is Valve (as in the video game company) anti-cheat software. It would not surprise me if they have a way to identify and report terrorist language and threats used in chat during gameplay on their servers. However, I can't see how the wide variety of topics which could be percieved as threating or terrorist related could be filtered for credibility - much less how reporting them to "the government" en masse would be in any way efficient or worthwhile. Also, I don't know why Valve anti-ceat would contact you via AIM - not to mention if it really were reporting to "the government", they would most likely specify a particular agency. "The government" is a little vague. :P

IN OTHER WORDS: Don't sweat it. Especially if it wasn't even on your computer. Most probably, your friend said some dumb things playing Half-Life 2 and got himself in trouble. This is not very probable!
Nausicaa Reviewed by Nausicaa on . wtf...im sketched... ive been talking to my friend online about bud all night, and a fw seconds ago he got an IM saying 'your proxy is being monitored, we are monitoring your id' the sn was like VACsecured or something. im sketched out, could i get in trouble some how...is that real? legal? wtf!? Rating: 5