Mr. Dean's lessons for practical libertarianism:
First, recognize the legitimate role of government in our flawed world.
Second, in the world of politics, take what you can get. You can always come back for more.
The biggest stumbling block to Libertarians in the US is that their leadership tries to push for everything at once. Anything that falls short is seen as a failure. A foreign example would be the publication of the Occupational Safety Guide for Prostitutes in New Zealand (yes, Samizdata is one of my favorite poaching grounds). Some of the commenters complained at how the regulatory impulse had tainted the gain of prostitution being legalized. Those folks are perfectly correct to complain, yet one should not disdain the gain made in the process. As Mr. Dean said, "You can always come back for more."
And a word to Mr. Julian Morrison, Samizdata commentor: Treating terrorism as a criminal matter has been so effective for the previous twenty years. [/sarcasm] While Al Qaeda may not have any obvious state sponsors, its aims (primary among which is the expulsion of Western influence in the Middle East) are largely coincident with several states in the region. If any state aids such a group in accomplishing such an attack on the United States or its allies, then it should be read that the complicit state should be seen as committing an act of war utilizing irregular forces. The conflict that is facing us today is of a different nature than has been seen before. So different, that I believe that we may need to revisit the concept and definition of "war" to properly describe it.