Warning of a "long fight" in Afghanistan, Gates announced his intention to escalate the U.S. military commitment there, saying in early December, “I do believe there will be a requirement for a sustained commitment here for a protracted period of time. How many years that is, and how many troops that is, nobody knows at this point.”
Certainly he's correct, in that 'nobody knows' what the effect and result will be, but, I'll wager history can make a pretty good guess.
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