Rolling Stone magazine may have done in Gen. Stanley McChrystal, but the Rolling Stones may have it had right when they sang, "You can't always get what you want... But if you try sometimes you might find
you get what you need."

So it is with the president’s selection of Generals Petraeus and Mattis to lead the war in Afghanistan. These two men, working together are the one – and only – team that just might turn a near certain defeat in Afghanistan into a victory.

Both men are a contrast of opposites. Marine Gen. James N. “Mad Dog” Mattis, whom the Pentagon announced on Thursday would be taking over U.S. Central Command, is a tough talking Marine from the Pacific Northwest, a military historian and scholar. General David Petraeus is measured, diplomatic, the Prince of the Powerpoint presentation, and a man who survived a near fatal chest wound and was jogging and doing push-ups a few weeks later.

But they both have one thing in common -- they both know how to win wars. Especially these kind of wars.
Petraeus and Mattis, in earlier commands in Iraq and Afghanistan, abandoned classical warfighting techniques because they weren’t working. They listened to their junior officer corps and concluded we were fighting class insurgencies. So they innovated. They resurrected and revised counterinsurgency strategy. They rewrote the Army Field Manual.

They didn’t sugar coat the situation to their political masters, and they didn’t hold out false expectations. They told it like it was, they said what they needed to do the job, and then they turned it around.

Last year I embedded with the 101st Airborne Division in Eastern Afghanistan. I also traveled off the bases and met with Afghan political and military leaders, as well as heads of international NGO’s. I asked everyone I met the same questions: What’s your goal in Afghanistan? What’s America’s goal? What constitutes victory? Every single person had different answers.

I came away from Afghanistan with a sinking feeling that there was no way we could win a war if we couldn’t even define the mission.

But three weeks ago I attended a small dinner with Gen. Mattis. I saw in him what I had seen before in Petraeus – someone who has no illusions about the difficulties ahead in Afghanistan, but who has the ability, intelligence and integrity to figure out what needs to be done, and then do it.

With Petraeus and Mattis, President Obama may finally have found the right team for the Iraq and Afghanistan wars. It will be hard but -- as General Petraeus is fond of saying -- hard is not hopeless. And if they can't succeed in Afghanistan, then no one can.

And, if anyone is worried that Mattis, or any general, might say something a little too blunt in public, the solution is simple. Just put a woman officer on the staff. A strong woman officer in the inner circle would never have tolerated the kind of trash talk that McChrystal and his aides engaged in.

And very few senior officers would dare behave that way in front of any woman, even if she were a fellow officer. Sexist? Maybe. But with generals as with wars, what we really care about is results.

Kathleen Troia "K.T." McFarland is a Fox News National Security Analyst and host of FoxNews.com's DefCon 3. She is a Distinguished Adviser to the Foundation for the Defense of Democracies and served in national security posts in the Nixon, Ford and Reagan administrations. She wrote Secretary of Defense Weinberger’s November 1984 "Principles of War Speech" which laid out the Weinberger Doctrine. Be sure to watch "K.T." every Monday at 10 a.m. on FoxNews.com's "DefCon3" already one of the Web's most watched national security programs. 

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