Is it still possible to win Wars?

On a daily basis we are informed about wars taking place from Central Africa to Central Asia; about attitudes of power politics from the Near East to the Far East; about power struggles in the Ukraine, Thailand or Venezuela. 

But the basic question is: Can wars still be won? We all remember the declaration of George W. Bush on the USS Abraham Lincoln : "Mission accomplished". Two years earlier, the Taliban were overthrown within weeks and the Kosovo became independent after a
NATO bombing campaign against Serbia.

But taking a closer look, the situation is more complicated: The future of Afghanistan is still not clear after 13 years of warfare; people still get killed in Iraq almost on the daily basis; the Kosovo-problems are not solved; and Libya after the overthrown of Gaddaf gets more and more anarchic.