Since it's headline time, I saw this earlier and wondered why it couldn't be considered treason. They'd basically be conspiring against America in some form or fashion. I say they should lose their citizenship at the very least.
http://news.yahoo.com/mississippians-charged-trying-join-islamic-state-081252703.html
It can't be considered treason because they didn't actually succeed in "adhering themselves to the enemy" or "giving them aid and comfort."
It's too bad there's no law against stupidity. Or maybe that's good, because then we'd have 80 of the populace locked up.
So, you don't think it would be covered under the sud-head 'subversive activities' of the code?
https://www.law.cornell.edu/uscode/text/18/part-I/chapter-115
I don't think locking them up will help either... and as you already pointed out, we'd have to let some of those pot dealers out to make room. Yet another discussion.
"Subversive Activities" isn't a sub-heading, simply a related category of activities with lesser significance. 18USC defines both crime and the general minimum and maximum punishments, but doesn't provide the parameters for conviction of the crime, which is left to precedent. This makes it tricky to define "subversive activities" simply because of the constitutional guarantees of freedom of speech and assembly. Historically, it's been difficult to successfully prosecute subversion in the US except in wartime.
As for locking them up, I kinda feel that's the worst punishment we can levy. Lock a couple of twenty-somethings in supermax, and in a couple of years the pointlessness of their existence sinks in - and they still have decades to go. Execution suits the zealot's mindset, which needs the grand demonstration - it needs action. Lock down and regiment the zealots existence, and there is nothing to satisfy that hunger. That's sheer torture.