What many people don't understand, we already give citizenship preferences to foreign nationals who complete honorable service in our US armed forces. In fact, we have seen tens of thousands, perhaps hundreds of thousands of foreign nationals that have attained citizenship in this very way over the last 60+ years. Of course, all those people did it legally. They asked for the permission to come and serve. It was given, and they held up their end of the bargain.
The military service option in the so-called "dream act" is complete bullsh*t. It actually disenfranchises all those young men (and women) who dreamed of coming to America, and did it the right way.