When our credit limit has been reached. When exactly that is I don't know, but at $9T and a dollar that has lost ~40% our creditors are getting very worried and have made noises that they won't allow it to drop much more without off loading our debt.
I think it was definitely a diversion to pull us of recession, providing the illusion of a healthy (war) economy. But it is only an illusion that is now fading. The recession is coming back with a vengeance, because now it is fueled by much more debt than in 2003, we're at or approaching our credit limit, and we can't devalue the currency much more.
And the War on Terror was a diversion away from pressing social issues like health care, education, jobs, environmental issues, renewable energy. So we have a trillion less dollars to spend on programs that matter.
Other reasons for Middle East war are allowing multinational oil companies to reassert control of ME oil, and providing welfare for the military industrial complex. That's "Why We Fight". See the documentary.
http://www.imdb.com/title/tt0436971/