Many libertarians believe that the US should withdraw troops from Iraq, not engage Iran and not get involved in political impasse anywhere in the world that may have led to war overseas.
Whereas, it might appear to be prudent to take a favorable view of isolationism, it should also be noted that historically, that can prove to be detrimental to our national sovereignty.
The World is closer together now, and things which affect others, to affect us here in the States.
The current actions in Iraq have drained much of our national treasury and we have spent far too much on this event.
Obviously, at this point we need to replenish our National Treasury, thus we should do so by collecting the oil there, using that to pay off the debt and the profits to rebuild Iraq and fund our future efforts there.
If the US took such a view in the world, we would leave many of our allies vulnerable and they would soon be conquered by other emerging super powers.
Thus, to take such an approach would be highly irresponsible.
Now, I realize that folks like Republican Ron Paul and Independent Ralph Nader, echo the comments of Barack Obama, but if we fail to learn from history, surely someone will be doomed and if it is not us, then it will be one of our trading partners or allies, and to not understand that or worse not care is unacceptable and completely irresponsible for the top leader of the free world and commander in chief of the United States of America.
Surely, you can see that?