What's wrong with the following as a 'justifiable rationale'?

The hijackers did their planning in Germany and learned how to fly in the US…

“Al Qaeda and its allies — the terrorists who planned and supported the 9/11 attacks — are in Pakistan and Afghanistan. Multiple intelligence estimates have warned that al Qaeda is actively planning attacks on the United States homeland from its safe haven in Pakistan. And if the Afghan government falls to the Taliban — or allows al Qaeda to go unchallenged — that country will again be a base for terrorists who want to kill as many of our people as they possibly can.”
…
As President, my greatest responsibility is to protect the American people. We are not in Afghanistan to control that country or to dictate its future. We are in Afghanistan to confront a common enemy that threatens the United States, our friends and our allies, and the people of Afghanistan and Pakistan who have suffered the most at the hands of violent extremists.

So I want the American people to understand that we have a clear and focused goal: to disrupt, dismantle and defeat al Qaeda in Pakistan and Afghanistan, and to prevent their return to either country in the future. That's the goal that must be achieved. That is a cause that could not be more just. And to the terrorists who oppose us, my message is the same: We will defeat you.

http://www.whitehouse.gov/the_press_office/Rema…

And what is being offered as rationale for a pullout? Substance free rhetoric like “same old failed policies” and “endless war”? I don't have a Webster's handy but 7 years is not “endless”. And how have those policies failed? Are you proposing that it is a coincidence that major terror attacks against the US homeland have not occurred for 8 years now?

I have serious concerns about trying to turn Afghanistan into some type of model state, but to decide to hand the jihadists a huge victory over a 50K troop increase seems foolish in the extreme. Obama needs to quit trying to appease the hypocritical left and execute on his own stated policies.

We should be preoccupied with details like that, that matter, rather than “endless war” loser-myths.