Wars waged in self-defense, of course; but also, in limited circumstances, wars waged against murderous tyrants whom the civilized world deemes necessary to be toppled (e.g. Adolph Hitler, Benito Mussolini, Hideki Tojo) and terrorists. Indeed, if you want to protect your own people and other civilized nations, you must struck and defeat terrorists BEFORE they can do harm to anyone. And that IS a Just War.
It falsely claims that the GWOT has cost $4 trillion to date, when the real cost of the Afghan and Iraqi wars has been a little over $1 trillion to date, and that cost will stop growing in FY2015 after the last American troops withdraw from Afghanistan.