Everybody says Liberty, but how many of those people are neocons or vote democrat? Liberty over security, but we most hurt people's economic liberty and hook up the poor with a bunch of free stuff, or Liberty over security but we should let the NSA look into all our emails so we can be safe from terrorists
On a personal level, with liberty you have the freedom to create your own security. But government is allowing that less and less. On an international terrorist level, our government wouldn't need to be spying on it's citizens if it wasn't allowing anything and everyone to cross our borders or get visas. But our government just keeps letting them pour in. On a national homegrown variety of terrorists, maybe the first two points have something to do with that.